3-Aryl-5,6-dihydro-1,4,2-oxathiazines and their oxides

This invention relates to derivatives of 3-aryl-5,6-dihydro-1,4,2-oxathiazines and their oxides, and to the use of such derivatives as herbicides, fungicides, and plant dessicants and defoliants. The invention also relates to methods of preparing these chemicals.
Dihydro 1,4,2-oxathiazines are little known in the chemical literature. A multi-substituted compound, N-(5,6-dihydro-5,6-dimethyl-3-phenyl-1,4,2-oxathiazine-6-yl)acetamide, was reported in Tetrahedron Letters, 1972, p. 5267, and a tetrahydro compound was described in J. Org. Chem. 30:949 (1965). However, no utility was disclosed for these compounds.
The chemicals of this invention are represented by the general formulae below, and possess herbicidal activity, fungicidal activity and plant desiccating and defoliating activities. ##STR1## wherein n is 0, 1 or 2, R.sup.1 is hydrogen, C.sub.1 -C.sub.4 linear or branched alkyl or benzyl, and R has one of the following values:
phenyl or naphthyl;
phenyl substituted with 1 or 2 of the following groups:
hydroxyl
halo
C.sub.1 -C.sub.12 alkyl
C.sub.5 -C.sub.6 cycloalkyl
trihalomethyl
phenyl
C.sub.1 -C.sub.5 alkoxy or alkylthio
tetrahydropyranyloxy
phenoxy
C.sub.2 -C.sub.5 alkylcarbonyl
phenylcarbonyl
C.sub.1 -C.sub.4 alkylsulfinyl
C.sub.1 -C.sub.4 alkylsulfonyl
carboxy or its alkali metal salt
C.sub.2 -C.sub.5 alkoxycarbonyl
C.sub.2 -C.sub.5 alkylaminocarbonyl
phenylaminocarbonyl
tolylaminocarbonyl
morpholinocarbonyl
amino
nitro
cyano or
dioxolanyl;
pyridinyl;
thienyl provided n is not 2;
furanyl;
furanyl substituted with 1 to 3 of the following groups:
C.sub.1 -C.sub.4 alkyl and
C.sub.2 -C.sub.5 alkoxycarbonyl.
In preferred compounds of the foregoing formula, R.sup.1 is hydrogen or C.sub.1 -C.sub.4 linear or branched alkyl and R has one of the following values:
phenyl;
phenyl substituted with 1-2 of the following groups:
F, Cl, Br, except not 2-Cl or 2,4-Cl.sub.2 if n is 2
C.sub.1 -C.sub.4, except p-t-alkyl if n is zero
CF.sub.3
phenyl except if n is 2
C.sub.1 -C.sub.5 alkoxy
C.sub.2 -C.sub.5 alkylcarbonyl
C.sub.2 -C.sub.5 alkoxycarbonyl except 4-alkoxycarbonyl if n is zero
amino
nitro or
cyano;
3- or 4-pyridinyl provided n is not 2
thienyl provided n is not 2;
furanyl;
furanyl substituted with 1 to 3 of the following groups:
methyl or
C.sub.2 -C.sub.3 alkoxycarbonyl.
In more preferred compounds of the above formula, R.sup.1 is hydrogen or methyl and R has one of the following values:
phenyl provided n is not 2;
phenyl substituted with 1 or 2 of the following groups:
F, Cl, Br, but not 2-Cl or 2,4-Cl.sub.2 if n is 2
n-C.sub.1 -C.sub.4 alkyl
CF.sub.3
C.sub.1 -C.sub.2 alkoxy
C.sub.2 -C.sub.5 alkylcarbonyl, provided n is 1
C.sub.2 -C.sub.3 alkoxycarbonyl provided n is 1 or 2
nitro or
cyano;
3- or 4-pyridinyl provided n is 0 or 1;
thienyl provided n is 0 or 1;
furanyl;
furanyl substituted with 1 to 3 methyl groups, provided n is 1 or 2.
Compounds of the invention may be used for control of various grasses and broadleaved weeds including pigweed (Amaranthus retroflexus L.), velvetleaf (Abutilon theophrasti Medic.), jimsonweed (Datura stramonium L.), tall morning-glory (Ipomoea purpurea (L.) Roth), barnyardgrass (Echinochloa crusgalli (L.) Beauv.), green foxtail (Setaria viridis (L.) (Beauv.) giant foxtail (Setaria faberi Herrm.), crabgrass (Digitaria ischaemum (Schreb.) Muhl.) and switchgrass (Panicum virgatum L.).
Chemical harvest aids are used for a wide variety of primary effects, including the defoliation of the crop plant; the desiccation of its leaves, stems, and other aerial organs; the control of late-season regrowth (e.g. cotton); the concentration of crop maturity providing more efficient harvesting.
Under normal conditions, many crop plants do not mature uniformly or in a timely fashion, so that efficient, optimum harvest is difficult, either due to equipment scheduling or to weather. Crops such as cotton, potato, sunflower, seed legumes and other oilseed crops require either desiccation or defoliation before harvest can be effectively accomplished. Cotton is an example of a crop with a long history of successful harvest aid use. When cotton is adequately defoliated, mechanical pickers can operate more effectively. If the crop is not defoliated, the leaves can interfere with the picking mechanism. Also, leaves can contaminate the cotton lint with trash or green stain, which reduces the quality of the fiber or reduces the efficiency of the ginning process. Likewise, potato vines need to be desiccated for efficient mechanical digging. In addition, upon desiccation of potato leaves and haulms, the tuber skin matures and becomes less susceptible to damage from the digger and post-harvest handling. Seed legumes and sunflowers are also mechanically harvested, and this process is facilitated if the leaves are removed or desiccated. As with cotton and potato, such defoliation or desiccation also ripens the seed uniformly, accelerates the rate of fruit maturation, and conditions the pod or head for easy harvest.
Compounds of this invention have been found to have surprising utility as harvest aid chemicals. Specifically, when applied to the foliage of crop species, they cause desiccation and/or defoliation of the leaves, can cause desirable changes in the fruiting form (e.g. cotton boll), and may alter the re-growth of the plant.
Applications of the compounds may be in the form of aqueous solutions or suspensions applied to the target tissue. Compounds of this invention may be used alone, in combination with one or more other oxathiazine derivative described here, or as a tank mix with other harvest aid chemical compounds or spray adjuvants (such as surface-active agents, stickers, emulsifiers, or extenders).
In addition, the chemicals described for this invention possess antifungal properties which are useful for the control of plant diseases such as Rice Blast, Bean Rust, Tomato Early Blight, Cercospora Leaf Spot or similar diseases. Growth inhibition tests indicate a broad spectrum of activity against other disease-producing fungi such as Alternaria, Sclerotium, Piricularia, Pythium, Phytophthora, Fusarium.
Two methods of synthesizing the chemicals of this invention have been discovered. One of these is outlined in Scheme I below and utilizes aromatic aldehydes as starting materials. ##STR2##
N-hydroxyarylcarboximidoyl chloride (II) is treated with 2-chloroethanethiol in the presence of two equivalents of base or suitable hydrogen chloride scavenger to produce 3-aryl-5,6-dihydro-1,4,2-oxathiazine (I, n=0). The II intermediate may be readily made by known methods by converting an aldehyde of the formula RCHO to its corresponding oxime (RCH.dbd.NOH) in the presence of H.sub.2 NOH and subsequent chlorination with chlorine or t-butyl hypochlorite in methylene chloride or chloroform as the solvent. If only one equivalent of base is used, the intermediate 2-chloroethyl N-hydroxybenzene-carboximidothioate derivative is isolated. This intermediate will give the oxathiazine when treated with a base.
Oxidation of oxathiazines with peroxyacetic acid or m-chloroperoxybenzoic gives the oxides (I, n=1 or 2).
Scheme II below outlines the second method of preparation, which uses arylcarbodithioate esters. ##STR3##
Treatment of a carbodithioate ester (IV) with hydroxylamine results in the liberation of ethyl mercaptan and the formation of N-hydroxyarylthioamide (Va) which enolises to N-hydroxyarylcarboximidothioic acid (Vb). Formation of the oxathiazine is then accomplished by reacting with vicinal dihaloalkane, ##STR4## (R.sup.1 and X as previously described) in the presence of two equivalents of base. A minor impurity is sometimes obtained in this reaction. For example, when two molecules of N-hydroxycarboximidothioic acid (Vb) react with one molecule of 1,2-dibromoethane, 1,2,-ethanediyl bis(N-hydroxyarylcarboximidothioate) is produced and can be extracted from the reaction by washing with dilute aqueous sodium hydroxide.
In Scheme I, the reaction of compound II with compound III for the preparation of the desired oxathiazine of this invention may be carried out at a temperature of minus 10.degree. to plus 20.degree. C. Usually, the reaction takes about 0.5-6 hours for completion but ordinarily does not take longer than 3 hours.
In Scheme II, the Step I reaction is performed at from 0.degree. to 30.degree. C., usually at 10.degree.-25.degree. C., and it may take 0.5-2 hours, generally 0.5-1 hour to form the Va/Vb equilibrium product. In Step 2, a temperature of 0.degree.-100.degree. C. may be employed although a 20.degree.-80.degree. C. temperature range is more preferred. The reaction usually takes from 0.5 to 5 hours, but in many cases completion can be obtained within 3 hours. As solvents, C.sub.1-C.sub.10 aliphatic alcohols may be used or aprotic solvents such as dimethylformamide or dimethylsulfoxide.
If so desired, intermediate compounds suitable for making the chemicals of this invention may be prepared having the structural formula RC(.dbd.NOH)SCH.sub.2 CH.sub.2 Cl by using Scheme I of this invention wherein R has the meanings of claim 1, R.sup.1 is hydrogen and n is 0, using only one equivalent of base such as alkali metal C.sub.1 -C.sub.10 alkoxide, alkylamines, alkanolamines, pyridine, morpholine and similar organic bases.

The preparation of the compounds can best be illustrated by the following specific examples.
Compound numbers are in parenthesis (c.f. Tables 1 to 4).
EXAMPLE 1
2-Chloroethyl 2-chloro-N-hydroxybenzenecarboximidothioate
2-Chlorobenzaldoxime (46.7 g, 0.3 mol) in chloroform (350 ml) was cooled and stirred in an ice/salt bath. Chlorine gas was bubbled into the reaction until an excess was present. Excess chlorine and solvent were removed and the remaining 2-chloro-N-hydroxybenzenecarboximidoyl chloride dissolved in ether (250 ml). Solutions of triethylamine (30.3 g, 0.3 mol) in ether (50 ml) and 2-chloroethanethiol (29 g, 0.3 mol) in ether (50 ml) were added simultaneously with stirring and cooling. After the addition, the reaction was allowed to warm to room temperature and left overnight. Water was added, and the ether layer was washed with additional water, then dried with anhydrous magnesium sulphate. Evaporation left a white solid, 2-chloroethyl 2-chloro-N-hydroxybenzenecarboximidothioate, m.p. 115.degree.-117.degree. C., (Found: C, 43.29; H, 3.58; N, 5.59. C.sub.9 H.sub.9 Cl.sub.2 NOS requires C, 43.21; H, 3.62; N, 5.60).
The following compounds of this type were prepared in a similar manner.
______________________________________ ##STR5##V W X Y Z m.p. .degree.C.______________________________________H H Cl H H 110-117Cl H Cl H H 104-106H H CH.sub.3 H H 118-119CH.sub.3 H H CH.sub.3 H 86-96______________________________________
EXAMPLE 2
3-(2-Chlorophenyl)-5,6-dihydro-1,4,2-oxathiazine (3)
2-Chlorethyl 2-chloro-N-hydroxybenzenecarboximidothioate (25 g, 0.1 mol) was added to a cold solution of sodium (2.3 g) in ethanol (150 ml). An exotherm was observed. The reaction was left at room temperature overnight, then the ethanol was removed, the product extracted with ether, the ether solution washed with water, dried and evaporated to leave an oil. Distillation b.p. 121.degree. C. at 0.02 mm (2.67 pa) gave an oil which solidified, 3-(2-chlorophenyl)-5,6-dihydro-1,4,2-oxathiazine, m.p. 51.degree.-52.degree. C. (Found: C, 50.30; H, 3.73; N, 6.57. C.sub.9 H.sub.8 ClNOS requires C, 50.58; H, 3.77; N, 6.55).
EXAMPLE 3
5,6-Dihydro-3-(4-pyridinyl)-1,4,2-oxathiazine (11)
4-Pyridinecarboxaldehyde oxime (30.6 g, 0.25 mol) was chlorinated in chloroform (350 ml) as described in Example 1 to produce N-hydroxy-4-pyridine-carboximidoyl chloride which was suspended in ether (500 ml) containing 2-chloroethanethiol (26.9 g, 0.25 mol). With ice bath cooling, triethylamine (5.1 g, 0.5 mol) was added dropwise. After the addition, water was made, the suspended solid, crude 2-chloroethyl N-hydroxy-4-pyridinecarboximidothioate was collected on a filter and dried. This crude ester was added to a solution of sodium ethoxide (from 5.75 g sodium in 500 ml ethanol), and the reaction mixture stirred for 4 hours. Water was added and the product was extracted with ether to give 5,6-dihydro-3-(4-pyridinyl)-1,4,2-oxathiazine, mp 80.degree.-82.degree. C., (found: C, 53.16; H, 4.56; N, 15.07. C.sub.8 H.sub.8 N.sub.2 OS requires C, 53.33; H, 4.48; N, 15.55).
EXAMPLE 4
5,6-Dihydro-3-[3-trifluoromethyl)phenyl]-1,4,2-oxathiazine (45)
Ethyl 3-(trifluoromethyl)benzenecarbodithioate (24.7 g, 0.1 mol) was dissolved in ethanol (50 ml) in which was suspended hydroxylamine hydrochloride (7 g, 0.1 mol). With stirring, triethylamine (10.1 g, 0.1 mol) in ethanol (25 ml) was added dropwise. After 5 hours, ethyl mercaptan was removed under reduced pressure through a KOH scrubber. 1,2-Dibromoethane (19 g, 0.1 mol) was added to the reaction mixture followed by dropwise addition of triethylamine (30 ml) in ethanol (50 ml). A white precipitate formed. After the addition was complete, the reaction mixture was warmed until it was homogeneous, then left at room temperature overnight. Water was added, the product extracted into ether, the ether solution washed with dilute sodium hydroxide (2N approx.), then water, dried over anhydrous magnesium sulphate and evaporated to leave an oil which was distilled to give 5,6-dihydro-3-[3-(trifluoromethyl)phenyl]-1,4,2-oxathiazine, bp 113.degree./0.2 mm.
EXAMPLE 5
5,6-Dihydro-3-(2-furanyl)-1,4,2-oxathiazine (31)
Methyl 2-furancarbodithioate (30 g, 0.2 mol) was converted to 5,6-dihydro-3-(2-furanyl)-1,4,2-oxathiazine, an oil, bp 128.degree.-129.degree. C. at 1.3 mm (173 Pa), preparation similar to Example 4). The sodium hydroxide wash from the ether extract was acidified. An amber oil separated out and on standing, solidified. This solid was collected, washed with ether, dried and found to be 1,2-ethandiyl bis(N-hydroxy-2-furancarboximidothioate), mp 147.degree.-150.degree. C. (Found: C, 45.80; H, 4.08; N, 8.62. C.sub.12 H.sub.12 N.sub.2 O.sub.4 S.sub.2 requires C, 46.16; H, 3.87; N, 8.97.)
EXAMPLE 6
5,6-Dihydro-3-(3-fluorophenyl)-1,4,2-oxathiazine, 4-oxide (28)
5,6-Dihydro-3-(3-fluorophenyl)-1,4,2-oxathiazine (19.7 g, 0.1 mol) was dissolved in chloroform, 50 ml). 3-Chloroperoxybenzoic acid (21 g) dissolved in chloroform (200 ml) was added dropwise at such a rate that the temperature of the reaction mixture remained at between 25.degree. to 30.degree. C. After the addition was complete, the reaction was left stirring at room temperature overnight. Saturated aqueous sodium bicarbonate was added and stirred until all gassing ceased. The chloroform solution was washed with water, dried over anhydrous magnesium sulphate and evaporated to leave a solid which was recrystallised from ether/ligroin, to give 5,6-dihydro-3-(3-fluorophenyl)-1,4,2-oxathiazine 4-oxide, mp 79.degree. C.
EXAMPLE 7
5,6-Dihydro-3-(3-chlorophenyl)-1,4,2-oxathiazine, 4-oxide (84)
5,6-Dihydro-3-(3-chlorophenyl)-1,4,2-oxathiazine (21.4 g, 0.1 mol) in methylene chloride (50 ml) was cooled with ice water. 3-Chloroperoxybenzoic acid (21 g, 85%) in methylenechloride (150 ml) was added dropwise the reaction was stirred and the temperature maintained in 10.degree. C. After the addition, the reaction was brought to ambient temperature and stirred overnight. After washing with aqueous sodium bicarbonate, water and then drying over anhydrous magnesium sulphate, evaporation of the solvent left a solid which was washed with ether and dried to leave 5,6-dihydro-3-(3-chlorophenyl)-1,4,2-oxathiazine, 4-oxide, mp 112.degree.-4.degree. C. (Found: C, 47.03; H, 3.43; N, 6.21. C.sub.9 H.sub.8 ClNO.sub.2 S requires C, 47.07, H, 3.51, N, 6.09.)
EXAMPLE 8
3-(2,6-Dichlorophenyl)-5,6-dihydro-1,4,2-oxathiazine, 4,4-dioxide (56)
3-(2,6-Dichlorophenyl)5,6-dihydro-1,4,2-oxathiazine was oxidised as in Example 6 except that two equivalents of 3-chloroperoxybenzoic acid were used. Thus, 3-(2,6-dichlorophenyl)-5,6-dihydro-1,4,2-oxathiazine 4,4-dioxide, mp 180.degree.-182.degree. C. was prepared. (Found: C, 38.40; H, 2.56; N, 5.02. C.sub.9 H.sub.7 Cl.sub.2 NO.sub.3 S requires C, 38.58; H, 2.51; N, 5.00.)
EXAMPLE 9
3-(3-Chlorophenyl)-5,6-dihydro-1,4,2-oxathiazine (26)
Ethyl 3-chlorobenzenecarbodithioate (106 g, 0.5 mol) and ethanol (400 ml) was treated with finely powdered hydroxylamine hydrochloride (36 g, 0.5 mol, 97%) with stirring, triethylamine (50.5 g, 70 ml, 0.5 mol) was added dropwise. A slight exotherm was observed. After the addition, the reaction was stirred for 11/2 hours. Ethyl mercaptan was removed using a scrubber and vacuum trap. 1,2-Dibromoethane (95 g, 0.5 mol) was added to the reaction and with stirring, triethylamine (101 g, 140 ml, 1 mol) added dropwise. The initial red colour was completely discharged. When the addition was complete, the reaction was refluxed for 1 hour, cooled to room temperature and the solvent removed to leave a solid. Water was added, the product extracted into ether which was subsequently washed successively with water, 5% potassium hydroxide, water and then dried over anhydrous magnesium sulphate. After evaporation, a white solid remained, 3-(3-chlorophenyl)-5,6-dihydro-1,4,2-oxathiazine, mp 65.degree. C.
EXAMPLE 10
3-(3-Fluorophenyl)-5,6-dihydro-1,4,2-oxathiazine (27)
2-Chloroethyl 3-fluoro-N-hydroxybenzenecarboximidothioate was made in a manner similar to that described in Example 1 using the following materials:
3-Fluorobenzaldehyde oxime (27.8 g, 0.2 mol)
2-Chloroethanethiol (21.5 g, 0.2 mol)
Triethylamine (40.8 g, 0.4 mol)
Ether (400 ml)
Cyclisation of 2-chloroethyl 3-fluoro-N-hydroxybenzenecarboximidothioate was accomplished as described in Example 2 using sodium (4.6 g) in ethanol (300 ml) to give 3-(3-fluorophenyl)-5,6-dihydro-1,4,2-oxathiazine, mp 47.degree.-9.degree. C. (Found: C,54.66; H,4.13; N,7.07. C.sub.9 H.sub.8 FNOS requires C,54.81; H,4.09; N,7.10).
EXAMPLE 11
5,6-Dihydro-3-(3-nitrophenyl)-1,4,2-oxathiazine (12)
5,6-Dihydro-3-(3-nitrophenyl)-1,4,2-oxathiazine, mp 114.degree.-5.degree. C., was prepared in a manner as described in Example 9 using the following materials:
Methyl 3-nitrobenzenecarbodithioate, (117 g, 0.55 mol)
Ethanol (250 ml)
Hydroxylamine hydrochloride (40 g, 0.55 mol)
1,2-Dibromoethane (40 ml)
Triethylamine (80 ml) and a further (160 ml).
EXAMPLE 12
3-(4-Chlorophenyl)-5,6-dihydro-1,4,2-oxathiazine (1)
2-Chloroethyl 4-chloro-N-hydroxybenzenecarboximidothioate (2.5 g, 0.01 mol) was cyclised with sodium (0.23 g) in ethanol (25 ml) as described in Example 2. 3-(4-Chlorophenyl)-5,6-dihydro-1,4,2-oxathiazine, mp 80.5.degree.-81.5.degree. C., was isolated. (Found: C,50.16; H,4.24; N,6.44. C.sub.9 H.sub.8 ClNOS requires C,50.58; H,3.77; N,6.55.)
EXAMPLE 13
(3-(4-bromophenyl)-5,6-dihydro-1,4,2-oxathiazine (70)
3-(4-Bromophenyl)-5,6-dihydro-1,4,2-oxathiazine, mp 114.degree.-5.degree. C., was made as described in Example 9 using the following materials:
Ethyl 4-bromobenzenecarbodithioate (130.5 g, 0.5 mol)
Ethanol (500 ml)
Hydroxylamine hydrochloride (97%) (36 g, 0.5 mol)
1,2-dibromoethane (45 ml)
Triethylamine (72 ml) and a further (140 ml).
EXAMPLE 14
3-(3,5-dichlorophenyl)-5,6-dihydro-1,4,2-oxathiazine (64)
3-(3,5-Dichlorobenzenecarbodithioate (50 g, 0.2 mol), mp 88.degree.-9.degree. C.
Ethanol 250 ml
Hydroxylamine hydrochloride 14.5 g, 0.2 mol
Triethylamine (28 ml) in ethanol (30 ml)
1,2-dibromoethane (25 ml)
Triethylamine (56 ml)
EXAMPLE 15
5,6-Dihydro-3-(2-thienyl)-1,4,2-oxathiazine (37)
5,6-Dihydro-3-(2-thienyl)-1,4,2-oxathiazine, mp 86.degree.-89.degree. C., was made as described in Example 9 using the following materials:
Methyl 2-thiophenecarbodithioate (35 g, 0.2 mol)
Ethanol (100 ml)
Hydroxylamine hydrochloride (14 g, 0.2 mol)
1,2-Dibromoethane (37.6 g, 0.2 mol)
Triethylamine (28 ml) and a further (56 ml)
EXAMPLE 16
Ethyl 4-(5,6-dihydro-1,4,2-oxathiazine-3-yl)benzoate (80)
Ethyl 4-(5,6-dihydro-1,4,2-oxathiazine-3-yl)benzoate, mp 69.degree.-70.degree. C. was prepared as outlined in Example 9 using the following:
Ethyl 4-[(methylthio)thioxomethyl]benzoate (83 g, 0.35 mol)
Ethanol (200 ml)
Hydroxylamine hydrochloride (97%) (25 g, 0.35 mol)
Triethylamine (50 ml) in ethanol (50 ml)
1,2-Dibromoethane (30 ml)
Triethylamine (100 ml).
EXAMPLE 17
3-(3-Chlorophenyl)-5,6-dihydro-5-(or 6)-methyl-1,4,2-oxathiazine (92)
3-(3-Chlorophenyl)-5,6-dihydro-5-(or 6)-methyl-1,4,2-oxathiazine, bp 145.degree. C. at 0.25 mm (33.3 Pa), was prepared as described in Example 9 using the following:
Ethyl 3-chlorobenzenecarbodithioate (43.2 g, 0.2 mol)
Ethanol 200 (ml)
Hydroxylamine hydrochloride (14.5 g, 0.2 mol)
1,2-Dibromopropane (40.5 g, 0.2 mol)
Triethylamine (28 ml) and a further (56 ml).
EXAMPLE 18
[(3-(5,6-Dihydro-1,4,2-oxathiazine-3-yl)]-N-phenylbenzamide (100)
3-(5,6-Dihydro-1,4,2-oxathiazine-3-yl)benzoic acid (15 g, 0.07 mol) was suspended in methylene chloride (200 ml). Thionyl chloride (10 ml) was added and the reaction was refluxed until homogenous and all gassing had ceased. The solvent was removed, the remaining oil was taken up in methylene chloride and treated portionwise with aniline (12.5 g, 0.12 mol). An exotherm was observed. After several hours, water was added, the organic material separated, washed successively with water, aqueous bicarbonate, dilute hydrochloric acid, water and then dried over anhydrous magnesium sulphate. Evaporation of the solvent left a solid which was recrystallised from ethanol to give crystals of 3-(5,6-dihydro-1,4,2-oxathiazin-3-yl)-N-phenylbenzamide, mp 149.degree.-150.degree. C. (Found: C,64.65; H,4.92; N,9.65. C.sub.16 H.sub.14 N.sub.2 O.sub.2 S requires C,64.42; H,4.73; N,9.39).
TABLE 1__________________________________________________________________________ ##STR6##COM-POUND V W X Y Z m.p. .degree.C. or bp.__________________________________________________________________________1 H H Cl H H 80.5-81.53 Cl H H H H 51-52, 121 at 0.02 mm (2.67 Pa)6 Cl H Cl H H 137-141.degree. at 0.05 mm (6.67 Pa)8 H H CH.sub.3 H H 125-128.degree. at 1.5 mm (200 Pa)9 CH.sub.3 H H CH.sub.3 H 139-140.degree. at 0.4 mm (53.3 Pa)12 H NO.sub.2 H H H 114-11513 H Cl Cl H H 77-7816 CH.sub.3 H H H H 160 at 3 mm (400 Pa)18 H H H H H 47-4926 H Cl H H H 6527 H F H H H 47-4930 H CH.sub. 3 H H H 52-5434 H H OCH.sub.3 H H 91-9235 H OCH.sub.3 H H H oil39 H H F H H 46-48; 90.degree. at 0.05 mm (6.67 Pa)47 Cl H H H F oil48 H H CN H H 115-11851 H H COCH.sub.3 H H 128-12954 Cl H H H Cl 96-9760 H H OC.sub.6 H.sub.5 H H 98-10062 H H COC.sub.6 H.sub.5 H H 125-12663 H H O(CH.sub.2).sub.3 CH.sub.3 H H 96-764 H Cl H Cl H 88-969 H H C(CH.sub.3).sub.3 H H 86-9070 H H Br H H 114-571 H H (CH.sub.2).sub.3 CH.sub.3 H Oil78 H H CF.sub.3 H H 110-180 H H CO.sub.2 CH.sub.2 CH.sub.3 H H 69-7079 H H CO.sub.2 H H H 22587 H CO.sub.2 CH.sub.3 H H H 65-645 H CF.sub.3 H H H 113.degree. at 0.2 mm (26.7 Pa)88 H H C.sub.6 H.sub.5 H H 147-15089 H Br H H H 95-9793 H CO.sub.2 H H H H 168-17198 H H SCH.sub.3 H H 104-10599 H H CONHC.sub.6 H.sub.4 H H 183-185 2-CH.sub.3100 H CONHC.sub.6 H.sub.5 H H H 149-150101 H H SOCH.sub.3 H H 116-117107 H H O2-Tetra- H H 93-94 hydropyranyl108 H H OCH.sub.2 CH.sub.3 H H 95-96109 H H OC.sub.5 H.sub.11 H H 93-9592.sup.(2) H Cl H H H 145/0.25 mm110 H H CO4-Mor- H H 125-126 pholinyl111 H CH.sub.3 NO.sub.2 H H 116-117115 H NH.sub.2 H H H 71-74116 H CO.sub.2 CH.sub.2 CH.sub.3 H H H 47-49117 H H CO.sub.2 CH.sub.3 H H 142-143118 H H CO.sub.2 K H H >250119 H H OH H H 160-161125 H COOK H H H >250126.sup.(1) H Cl H H H 51-54.5127 H H NO.sub.2 H H 168-170130 H CN H H H 70-72132 F H H H H 125/0.25 mm139.sup.(2) Cl H H H H oil140.sup.(3) H Cl H H H oil__________________________________________________________________________ .sup.(1) Methyl group on 6 position of the 1,4,2oxathiazine ring. .sup.(2) Methyl group on 5 or 6 position of the 1,4,2oxathiazine ring. .sup.(3) Methyl group on 5 position of the 1,4,2oxathiazine ring.
TABLE 2______________________________________ ##STR7##COM-POUND V W X Y Z m.p. .degree. C.______________________________________5 H H Cl H H 72-7515 H NO.sub.2 H H H 149-15319 H Cl Cl H H 104-728 H F H H H 78-8129 H H H H H 68-7032 H CH.sub.3 H H H 68-6936 H H OCH.sub.3 H H 109-11241 H OCH.sub.3 H H H 62-6442 H H CH.sub.3 H H 100-10246 H CF.sub.3 H H H 89-9052 H H COCH.sub.3 H H 159-16055 Cl H H H Cl 133-13561 H H OC.sub.6 H.sub.5 H H 155-15767 H H O(CH.sub.2).sub.3 CH.sub.3 H H 77-868 H Cl H Cl H 135-673 H H (CH.sub.2).sub.3 CH.sub.3 H H 6875 H H C(CH.sub.3).sub.3 H H 101-376 H H Br H H 113-582 H H CO.sub.2 CH.sub.2 CH.sub.3 H H 106-884 H Cl H H H 112-486 H H CF.sub.3 H H 142-591 H CO.sub.2 CH.sub.3 H H H 103-10495 H H C.sub.6 H.sub.5 H H 138-14496 H Br H H H 104-106102 H CONHC.sub.6 H.sub.5 H H H 158-160103 H H SOCH.sub.3 H H 140-142104 H H SO.sub.2 CH.sub.3 H H 160-163112 H H CONHC.sub.6 H.sub.4 H H 168-169 2-OCH.sub.3113 H H OC.sub.5 H.sub.11 H H 68-70120 H CH.sub.3 NO.sub.2 H H 156-158121 H H COmor- H H 182-183 pholinyl122 H H OCH.sub.2 CH.sub.3 H H 125-127133 H CN H H H 153-155134 H H COOCH.sub.3 H H 137-138135.sup.(1) H Cl H H H 95-99.5136 H H NO.sub.2 H H 190-193140 Cl H H H H 94-95141 F H H H H 102-104______________________________________ .sup.(1) Methyl group on 6 position of the 1,4,2oxathiazine ring.
TABLE 3__________________________________________________________________________ ##STR8##COMPOUND V W X Y Z m.p. .degree.C.__________________________________________________________________________4 Cl H H H H 125-1277 Cl H Cl H H 101.5-10217 H NO.sub.2 H H H 135-14020 CH.sub.3 H H H H 118-12025 CH.sub.3 H H CH.sub.3 H 85-8643 H H CH.sub.3 H H 131.5-132.549 H H CN H H 115-11853 H H COCH.sub.3 H H 142-14456 Cl H H H Cl 180-18257 H H H H H 98-9958 H Cl Cl H H 145-14759 H H Cl H H 89-9065 H Cl H Cl H 133-466 H H O(CH.sub.2).sub.3 CH.sub.3 H H 104-572 H H (CH.sub.2).sub.3 CH.sub.3 H H 88-9074 H H C(CH.sub.3).sub.3 H H 133-477 H H Br H H 147-881 H H CO.sub.2 CH.sub.2 CH.sub.3 H H 118-2083 H Cl H H H 102-485 H H CF.sub.3 H H 158-990 H CO.sub.2 CH.sub.3 H H H 101-10294 H H C.sub.6 H.sub.5 H H 142-14597 H Br H H H 99-102105 H H CONHC.sub.6 H.sub.4 H H 212-213 2-CH.sub.3106 H CONHC.sub.6 H.sub.5 H H H 162-163114 H H OC.sub.5 H.sub.11 H H 66-67123 H H COmorpho- H H 165-168 linyl124 H H OCH.sub.2 CH.sub.2 H H 123-124128 H CH.sub.3 NO.sub.2 H H 140-141129 H CF.sub.3 H H H 104-104.5137 H H COOCH.sub.3 H H 173-176138.sup.(1) H Cl H H H 123-126142 H CN H H H 155-159143 F H H H H 130-132__________________________________________________________________________ .sup.(1) Methyl group on 6 position of the 1,4,2oxathiazine ring.
TABLE 4______________________________________ ##STR9##COM-POUND R n m.p. .degree.C./bp.______________________________________14 2-pyridinyl 0 135-13723 2-pyridinyl 1 18010 3-pyridinyl 0 125-128 at 0.05 mm (6.67 Pa)24 3-pyridinyl 1 46-5121 4-pyridinyl 1 150-15822 4-pyridinyl 2 18533 2-furanyl 1 77-7844 2-furanyl 2 92-9337 2-thienyl 0 86-8938 2-thienyl 1 107-10940 2,4,5-trimethyl- 0 mp 35; bp 132/0.1 mm (13.3 Pa) 3-furanyl11 4-pyridinyl 0 80-8231 2-furanyl 0 128-129/1.3 mm131 4-ethyoxycar- 0 66-7 bonyl-3,5- dimethyl-2- furanyl______________________________________
All of the above compounds in Tables 1 to 4 were confirmed by elemental analysis and/or N.M.R. spectra and/or infrared spectra.
Compounds within the contemplation of this invention include the following (n being 0, 1 or 2):
______________________________________V W X Y Z n______________________________________H H CONHC.sub.4 H.sub.9 H H 0 or 1H H CONHCH.sub.3 H H 0 or 1H H CN H H 1H Cl Cl H H 1H Cl H H H .sup. 1.sup.1______________________________________ .sup.1 Methyl group on 5 position of the 1,4,2oxathiazine ring.
As indicated above, compounds of the invention are particularly useful in herbicidal, fungicidal, defoliant and desiccant applications, particularly in the form of an agricultural chemical formulation comprising an effective amount of the compound in admixture with a carrier therefor.
For herbidical (post-emergent or pre-emergent) applications, a preferred class of compounds are those of the general formula given above, in which R.sup.1 is hydrogen, C.sub.1 -C.sub.4 linear or branched alkyl or bnezyl, n is 0, 1 or 2 and R has one of the following values:
phenyl or naphthyl;
phenyl substituted with 1 or 2 of the following groups:
halogen except 2-Cl if n is 2
C.sub.1 -C.sub.12 alkyl
C.sub.5 -C.sub.6 cycloalkyl
trihalomethyl
C.sub.1 -C.sub.8 alkoxy (but not C.sub.4 -C.sub.8 alkoxy if n is zero or 2)
phenoxy
tetrahydropyranyloxy
C.sub.1 -C.sub.8 alkylthio
C.sub.1 -C.sub.4 alkylsulfinyl
C.sub.1 -C.sub.4 alkylsulfonyl
C.sub.2 -C.sub.5 alkylcarbonyl provided n is 0 or 1
carboxyl or its alkali metal salt
2- or 3-(C.sub.2 -C.sub.5 alkoxycarbonyl)
4-(C.sub.2 --C.sub.5 alkoxycarbonyl) provided n is 0 or 1
C.sub.2 -C.sub.5 alkylaminocarbonyl
morpholinocarbonyl
amino
nitro
cyano
dioxolanyl;
4-pyridinyl if n is zero or 1;
thienyl provided n is not 2;
furanyl;
furanyl substituted with 1 to 3 of the following groups:
C.sub.1 -C.sub.4 alkyl
C.sub.2 -C.sub.5 alkoxycarbonyl.
More preferred herbicidal compounds are those wherein:
R.sup.1 is hydrogen or C.sub.1 -C.sub.4 linear or branched alkyl and
if n is zero, 1 or 2,
R=phenyl substituted with 1 or 2 of the following groups:
3-CF.sub.3
n-C.sub.1 -C.sub.4 alkyl provided they are in 3- or 4-position;
3-pyridinyl;
furanyl;
furanyl substituted with 1 to 3 of the following groups:
methyl
C.sub.2 -C.sub.3 alkoxycarbonyl.
if n is zero or 1,
R=phenyl;
phenyl substituted with 1 or 2 of the following groups:
F or Cl
trifluoromethyl;
thienyl;
if n is 1,
R=phenyl substituted with 1 or 2 of the following groups:
4-Br
4-CF.sub.3
C.sub.1 -C.sub.5 alkoxy
3-nitro
3-cyano.
Still more preferred herbicidal compounds are those wherein:
R.sup.1 is hydrogen or methyl, and
if n is zero, 1 or 2,
R=phenyl substituted with 1 or 2 of the following groups:
4-Cl
3- or 4-(n-C.sub.1 -C.sub.3 alkyl);
if n is 1 or 2,
R=2-furanyl;
if n is 1,
R=phenyl;
phenyl substituted with 1 or 2 of the following groups:
3-Cl or 3-F
4-trifluoromethyl
3-methoxy
3-nitro
4-(C.sub.1 -C.sub.4 alkyl);
2-thienyl;
if n is zero or 1,
R=3-pyridinyl;
if n is zero,
R=phenyl substituted with one of the following groups:
2,4-Cl.sub.2
2-Cl
3-Cl
4-F
2-Cl-6-F.
For fungicidal applications, a preferred class of compounds are those of the formula given above, in which R.sup.1 is hydrogen, C.sub.1 -C.sub.4 linear or branched alkyl or benzyl, n is 0, 1 or 2, and R has one of the following values:
phenyl or naphthyl;
phenyl substituted with 1-2 of the following groups:
hydroxyl
halo
C.sub.1 -C.sub.12 alkyl
C.sub.5 -C.sub.6 cycloalkyl
trihalomethyl
phenyl
C.sub.1 -C.sub.5 alkoxy or alkylthio
C.sub.2-C.sub.5 alkylcarbonyl
phenylcarbonyl
C.sub.1 -C.sub.4 alkylsulfinyl
C.sub.1 -C.sub.4 alkylsulfonyl
carboxy or its alkali metal salt
C.sub.2 -C.sub.5 alkoxycarbonyl
C.sub.2 -C.sub.5 alkylaminocarbonyl
phenylaminocarbonyl
tolylaminocarbonyl
morpholinocarbonyl, except when n is zero
amino
nitro
cyano
dioxolanyl;
pyridinyl, except 4-pyridinyl if n is zero;
thienyl provided n is not 2;
furanyl;
furanyl substituted with 1 to 3 of the following groups:
C.sub.1 -C.sub.4 alkyl
C.sub.2 -C.sub.5 alkoxycarbonyl.
More preferred fungicidal compounds are those wherein:
R.sup.1 is hydrogen or C.sub.1 -C.sub.4 linear or branched alkyl, and
if n is zero, 1 or 2,
R=phenyl or naphthyl;
phenyl substituted with 1 or 2 of the following groups:
F, Cl or Br in 3- or 4-positions;
if n is 1 or 2,
R=phenyl substituted with 1 or 2 of the following groups:
3- or 4-(C.sub.1 -C.sub.4 alkyl)
3- or 4-trifluoromethyl
C.sub.1 -C.sub.4 alkoxy
phenoxy
C.sub.2 -C.sub.5 alkylcarbonyl
C.sub.2 -C.sub.3 alkoxycarbonyl
nitro
cyano;
if n is 1,
R=biphenylyl;
3-cyanophenyl;
4-pyridinyl;
thienyl.
Still more preferred fungicidal compounds are those in which,
R.sup.1 is hydrogen or methyl;
n is 1 or 2;
R is phenyl;
phenyl substituted with 1-2 of the following groups:
F or Cl
methyl
3-trifluoromethyl
3-methoxy
methylcarbonyl
3-methoxycarbonyl
4-methoxycarbonyl provided n is 1
4-ethoxycarbonyl
nitro;
2-thienyl if n is 1;
2-furanyl.
For desiccating plants, a preferred class of compounds are those in which R.sup.1 is hydrogen, C.sub.1 -C.sub.4 linear or branched alkyl or benzyl and
if n is zero, 1 or 2,
R=phenyl or naphthyl;
phenyl substituted with 1-2 of the following groups:
Cl or Br in the 3-position
C.sub.1 -C.sub.12 alkyl in the 3- or 4 position
3-trihalomethyl
C.sub.1 -C.sub.3 alkoxy or alkylthio
C.sub.1 -C.sub.4 alkylsulfinyl
C.sub.1 -C.sub.4 alkylsulfonyl
carboxy or its alkali metal salt
3-methoxycarbonyl
4-ethoxycarbonyl
amino
cyano
dioxolanyl;
3-pyridinyl;
4-nitrotolyl;
furanyl;
furanyl substituted with 1-3 of the following groups:
C.sub.1 -C.sub.4 alkyl
C.sub.2 -C.sub.5 alkoxycarbonyl;
if n is 1 or 2,
R=phenyl substituted with:
2-F or 4-Br
4-trihalophenyl
3-ethoxycarbonyl
4-methoxycarbonyl
4-nitro;
if n is zero or 1,
R=phenyl substituted with
2-Cl
2-methyl
2,5-(CH.sub.3).sub.2
C.sub.2 -C.sub.5 alkylcarbonyl
morpholinocarbonyl;
4-pyridinyl;
thienyl;
if n is zero,
R=phenyl substituted with
3-F
2,6-Cl.sub.2 or 2-Cl-6-F;
R=2-pyridinyl.
More preferred compounds for desiccating plants are those in which R.sup.1 is hydrogen or C.sub.1 -C.sub.4 linear or branched alkyl and
if n is zero, 1 or 2,
R=phenyl;
phenyl substituted with
3-(Cl or Br)
3,4-Cl.sub.2
3-methoxy
3-CF.sub.3 ;
3-pyridinyl;
furanyl;
if n is zero or 1,
R=phenyl substituted with:
2-(Cl or F)
3- or 4-(n-C.sub.1 -C.sub.4 alkyl)
2,5-(CH.sub.3).sub.2
3-trifluoromethyl
3-methoxycarbonyl;
4-pyridinyl;
thienyl;
if n is zero,
R=phenyl substituted with 2-methyl;
if n is 1 or 2,
R=phenyl substituted with 4-CF.sub.3 ;
if n is 1,
R=3-nitrophenyl.
For defoliating plants a preferred class of compounds are those in which R.sup.1 is hydrogen, C.sub.1 -C.sub.4 linear or branched alkyl or benzyl and
if n is zero, 1 or 2,
R=phenyl;
phenyl substituted with 1-2 groups:
3- or 4-halo
3,5-Cl.sub.2
2-(C.sub.1 -C.sub.4 alkyl)
4-(C.sub.3 -C.sub.4 alkyl)
2,5-(CH.sub.3)
phenyl
3-methoxy
4-(C.sub.2 -C.sub.4 alkoxy)
C.sub.2 -C.sub.5 alkylcarbonyl
3- or 4-carboxy, alkali metal salt
4-methoxycarbonyl
C.sub.2 -C.sub.5 alkylaminocarbonyl
phenylaminocarbonyl
amino
3-nitro
3-cyano;
3- or 4-pyridinyl;
furanyl;
n is zero or 1,
R=phenyl substituted with:
2-halo
2,4-dihalo
2,5-(CH.sub.3).sub.2
4-CF.sub.3
4-pentyloxy
3-(C.sub.2 -C.sub.3 alkoxycarbonyl)
morpholinocarbonyl;
thienyl;
n is 1 or 2,
R=phenyl substituted with:
3-CF.sub.3
4-methoxy
4-nitro
4-nitrotolyl
3,4-Cl.sub.2 ;
n is zero,
R=phenyl
phenyl substituted with:
2-halo
3-methyl
3,5-(CH.sub.3).sub.2
phenoxy;
furanyl substituted with methyl and ethoxycarbonyl;
n is 1,
R=phenyl substituted with:
2,6-Cl.sub.2
4-CH.sub.3
4-ethoxycarbonyl;
n is zero or 2,
phenyl substituted with tolylaminocarbonyl or 2-methyl.
More preferred compounds for defoliating plants are those in which R.sup.1 is hydrogen or C.sub.1 -C.sub.4 linear or branched alkyl and
if n is zero, 1 or 2,
R=phenyl substituted with:
3-halo
3,5-Cl.sub.2
3-methoxy
4-carboxy alkali metal salt
3-amino
3-nitro
3-cyano;
3- or 4-pyridinyl;
is n is zero or 1,
R=phenyl substituted with:
2-halo
4-(Br or Cl
2,4-Cl.sub.2
2,5-(CH.sub.3).sub.2 ;
2-thienyl;
if n is zero, 1 or 2,
R=phenyl substituted with:
3-CF.sub.3
3-CH.sub.3 -4-NO.sub.2
4-nitro
4-methoxy;
if n is 0,
R=phenyl substituted with:
phenoxy;
if n is 1,
R=phenyl substituted with
4-(C.sub.1 -C.sub.4 n-alkyl)
C.sub.2 -C.sub.4 alkoxy
4-methylcarbonyl
3-(C.sub.2 -C.sub.3 alkoxycarbonyl)
4-methoxycarbonyl.
For herbicidal applications, compounds of this invention may be added as a "tank mix" to other herbicide solutions so that the number of different weed species controlled in a single application will be increased.
The procedures for using the present oxathiazine derivatives as herbicides may be in accordance with conventional agricultural practice. The chemicals are ordinarily applied as formulations containing a carrier and/or surface-active agent. The formulation may contain more than one of the described oxathiazine derivatives if desired; other active herbicides may be included in the formulation as well.
Thus, the chemical may be impregnated on finely divided or granular inorganic or organic carriers such as attapulgite clay, sand, vermiculite, ground corn cobs, activated carbon or other granular carriers known to the art. The impregnated granules may then be spread on the soil as preemergence herbicides. Furthermore, the chemical may be formulated as wettable powders by grinding them into a fine powder and mixing them with an inactive powdered carrier to which a surface active dispersing agent has been added. Typical powdered solid carriers are the various mineral silicates, e.g., mica, talc, pyrophyllite and clays. The wettable powder may then be dispersed in water and sprayed on the soil surface or weeds. Similarly, soluble or emulsifiable concentrate may be prepared by first dissolving the chemical in a solvent. The choice of solvent depends on the solubility of the particular chemical. Commonly used solvents are acetone, methyl ethyl ketone, C.sub.1 -C.sub.8 alcohols such as methanol, ethanol, butanol, hexanol and 2-ethylhexanol; toluene, xylene, chloroform, furfuryl alcohol, phenol, naphtha, petroleum ether, kerosene or other aliphatic cycloaliphatic or aromatic solvents. usually, a surface active agent or dispersant is added to the solvent. The resultant concentrate is then dispersed in water and applied by spraying. Suitable surface active agents and dispersants are well known to those skilled in the art and reference may be had to McCutcheon's Detergents and Emulsifiers, 1980, Allured Publishing Corp., Ridgewood, N.J.; or Hoffman et al. U.S. Pat. Nos. 2,614,916, cols, 2 to 4 and 2,547,724, cols, 3 and 4, for example of appropriate surface active agents. The concentration of active chemical in the formulation may vary widely, e.g., from 1 to 95%. For use as a preemergence herbicide, the chemical is applied to soil which contains weed and crop seed (either to the surface of the soil or incorporated into the upper 2.5 to 7.6 cm of soil).
The most suitable rate of application in any given case will depend on such factors as soil type, soil pH, soil organic matter content, the quantity and intensity of rainfall before and after treatment, the air and soil temperature, light intensity and light duration per day. All of these factors have an influence on the efficacy of the chemicals for use as herbicides.
EXAMPLE 18
To illustrate herbicide efficacy of the described 3-aryl-5,6-dihydro-1,4,2-oxathiazines, 600 mg chemical was dissolved in 10 ml organic solvent to which 30 mg conventional emulsifying agent (e.g., ethoxylated sorbitan monolaurate "Tween 20" [trademark]) was added; in most cases acetone was used as the solvent. The solution was diluted to 100 ml with distilled water. Twenty milliliters of this 6000 ppm solution was diluted to 250 ppm with distilled water. The chemical was applied at the rate of 11.2 kg/ha (kilograms per hectare) by drenching 46 ml of the 250 ppm solution on the surface of soil in 11.4 cm diameter plastic pots which had been sown with the following weed seeds: velvetleaf (Abutilon theophrasti Medic.) or rough pigweed (Amaranthus retroflexus L.), jimsonweed (Datura stramonium L.), tall morningglory (Ipomea purpurea (L.) Roth), crabgrass (Digitaria ischaemum (Schreb.) Muhl) or switchgrass (Panicum virgatum L.), barnyardgrass (Echinochloa crusgalli (L.) Beauv.) and giant foxtail (Setaria faberi Herrm.) or green foxtail (Setaria viridis (L.) Beauv.). The percent control of the weeds compared to untreated checks was determined two weeks after treatment. TABLE 5 shows the results with the preemergence herbicides of the invention prepared in accordance with the above examples.
EXAMPLE 19
To illustrate effectiveness of the described oxathiazines as postemergence herbicides, the 6000 ppm solutions described under Example 18 were atomized with a number 152 DeVilbiss (trademark) sprayer, wetting the foliage to the drip point. The weeds, which are the same species as described under Example 18, were treated six days after emergence. The percent control was evaluated two weeks after treatment. TABLE 6 shows the results with postemergence herbicides of the invention.
TABLE 5__________________________________________________________________________PREEMERGENCE HERBICIDE ACTIVITIES OF OXATHIAZINES AT 11.2 kg/ha PERCENT WEED CONTROL PIGWEED CRABGRASS GIANT OR OR JIMSON MORNING BARNYARD OR SWITCH- GREEN***COMPOUND VELVETLEAF* WEED GLORY GRASS GRASS** FOXTAIL__________________________________________________________________________5 98 0 0 10 0 259 90 0 0 25 0 010 90 75 0 50 25 013 100 0 10 15 0 018 100 0 0 0 0 027 85 0 0 0 0 028 100 0 35 30 95 98***29 100 0 0 30 95 95***30 100 0 0 20 80 80***32 100 0 0 50 25 0***33 95 98 0 50 0 25***36 100 0 0 15 0 0***37 100 0 0 0 0 0***38 100 0 0 35 30 30***39 100 0 100 0 0 0***41 100 0 0 0 75 0***42 100 0 0 50 75 75***43 40 0 0 0 0 0***44 70 0 0 30 80 65***46 100 0 0 0 0 0***47 -- 95 0 0 100 100***54 -- 0 0 80 90** 100***55 -- 100 0 90 95** 75***56 -- 100 0 50 80** 25***67 0* 0 0 40 20** 80***68 0* 0 0 25 50** 95***73 0* 0 0 50 95** 50***75 0* 0 0 60 95** 95***76 0* 0 0 50 90** 95***78 0* 0 0 0 30** 50***84 0* 70 0 30 50** 0***86 0* 75 0 75 95** 95***122 0* 0 0 50 15** 60***129 100* 0 0 0 0** 90***133 0 0 0 50 30** 50***135 0* 0 0 75 90** 80***__________________________________________________________________________
TABLE 6__________________________________________________________________________POSTEMERGENCE HERBICIDE ACTIVITY OF OXATHIAZINES AT 6000 PPM PERCENT WEED CONTROL PIGWEED CRABGRASS GIANT OR OR JIMSON MORNING BARNYARD OR SWITCH- GREEN***COMPOUND VELVETLEAF* WEED GLORY GRASS GRASS** FOXTAIL__________________________________________________________________________1 100 90 5 95 100 1003 100 35 65 100 85 1005 100 100 100 100 100 1006 100 100 30 100 100 1007 0 0 5 10 5 58 100 100 90 100 100 1009 100 10 98 100 100 10010 100 0 20 95 95 9511 100 5 35 35 50 7512 50 0 10 25 10 013 100 0 10 15 0 015 100 50 98 95 80 3016 20 5 10 20 25 1517 25 5 10 10 5 518 100 20 45 90 75 5019 65 10 35 60 20 1020 0 0 0 10 0 021 100 5 25 60 95 5024 100 100 100 95 75 4525 5 5 5 25 10 1026 100 100 70 98 98 9527 100 5 15 98 100 9828 100 100 100 100 100 100***29 100 100 100 100 100 100***30 100 5 50 100 100 100***31 100 10 30 95 100 100***32 100 100 100 100 100 100***33 100 100 100 95 100 100***34 100 0 5 90 75 90***35 100 10 85 70 50 50***36 100 0 5 70 95 95***37 100 0 0 55 25 25***38 100 90 75 80 80 90***39 100 20 25 100 100 100***40 100 25 90 90 30 30***41 100 80 100 95 90 90***42 100 100 100 100 70 85***43 90 80 70 90 75 90***44 90 80 100 95 75 90***45 100 20 30 90 95 100***46 80 65 75 60 40 25***47 100 10 45 75 75 90***48 100 0 5 80 75 100***49 95 0 10 25 10 35***50 50 0 5 5 -- 5***51 100 0 5 5 -- 15***52 100 0 30 25 -- 50***54 -- 50 5 100 100** 100***57 25 0 45 55 -- 90***58 100 -- 85 50 25** 80***59 60 90 100 95 65** 95***60 0 0 0 20 0** 20***61 -- 0 0 45 -- 20***64 0* 0 0 5 0** 10***65 0* 0 0 10 0** 10***67 0* 0 5 45 5** 35***68 0* 0 25 70 20** 80***69 0* 0 0 5 0** 10***70 0* 0 25 95 0** 95***71 100* 0 20 100 0** 95***72 25* 0 55 75 0** 40***73 100* 100 100 100 10** 95***74 0* 0 0 15 0** 10***75 10* 0 10 80 0** 65***76 5* 0 25 50 0** 45***77 0* 0 20 30 5** 10***78 0* 0 50 80 30** 90***79 0* 0 0 10 -- --80 0* 0 5 75 -- --81 0* 0 5 0 -- --82 25* 25 75 80 -- --83 65* 25 75 95 -- --84 50* 25 60 100 -- --85 0* 0 35 90 -- --86 75* 20 75 100 -- --87 100* 0 30 95 -- --89 40* 0 0 35 0** 75***90 0* 0 75 80 90** 100***91 15* 0 85 65 5** 25***92 100* 90 85 100 100** 100***93 0* 0 5 15 0** 25***96 5* 0 20 70 0** 30***97 5* 0 20 55 5** 40***98 0* 0 0 20 0** 25***99 0* 0 5 0 0** 0**101 10* 0 20 15 0** 15***102 0* 0 5 0 0** 0***103 5* 0 15 30 0** 25***107 0* 0 5 15 0** 10***108 15* 0 40 60 5** 55***109 0* 0 0 0 0** 5***110 15* 0 25 65 5** 100***111 0* 0 0 0 0** 5***112 0* 0 5 10 0** 10***113 100* 0 100 100 10** 100***114 0* 0 10 70 0** 100***115 0* 0 0 10 0** 60***116 0* 0 5 40 15** 75***117 0* 0 0 5 0** 15***118 0* 0 0 40 0** 85***120 20* 15 45 5 0** 35***121 5* 5 10 45 0** 55***122 10* 50 80 90 0** 100***123 0* 0 5 35 0** 45***124 0* 0 5 25 0** 75***125 15* 0 5 45 0** 35***126 95* 5 35 25 55** 85***127 0* 0 15 0 -- --129 50* 0 30 90 95** 75***130 90* 0 20 95 5** 75***132 100* 0 50 100 20** 70***133 0* 0 20 80 5** 50***134 0* 0 30 75 0** 10***135 100* 0 15 95 85** 95***136 100* 85 100 100 70** 80***138 0* 0 0 10 9** 0***__________________________________________________________________________
Procedures for using the compounds of this invention as plant desiccants and defoliants may be in accordance with the state of the art in conventional agricultural practice. The active ingredient(s) may be included in one or more formulations suitable for use in conventional application equipment. Such formulations may be of several different physical and chemical types, any of which could be made by anyone familiar with the art. For instance, the active ingredient(s) may be formulated into a soluble or emulsifiable concentrate that is prepared by dissolving the active ingredient(s) in one or more suitable solvents, such as acetone, toluene, or other aliphatic or aromatic hydrocarbon, to which a dispersing agent has been added. Alternatively, the active ingredient(s) may be formulated as a wettable powder by grinding it into a fine powder and mixing it with an inactive powdered carrier, to which a dispersing agent has been added. Typical inactive powdered carriers include attapulgite clay, vermiculite, talc, corn cob, activated carbon, mica and pyrophyllite. Alternatively, a wettable powder may be formulated by spraying a solution of the active ingredient(s) in organic solvent onto the surface of an inactive powdered carrier as it is blended. The solvent is subsequently allowed to vaporize. The concentration of the active ingredient(s) in formulations of all types may vary widely, ranging from 0.1 to 95% active ingredient by weight.
Formulations bearing the active ingredient(s) may be dispersed in water and applied to target plants. Surface active agents may be added to the applied solution to increase its qualitative or quantitive range of activity. Suitable surface active agents are well known to those skilled in the art. Reference may be made to McCutcheon's Detergents and Emulsifiers (1980, Allured Publ. Co., Ridgewood, NJ) or to Hoffman et al in U.S. Pat. Nos. 2,614,916 (cols. 2 to 4) and 2,574,724 (cols. 3 and 4) for examples of appropriate surface active agents.
The most suitable dosage of application of the active ingredient(s) and the type and amount of adjuvant substances to be added to the spray solution will depend on a number of factors, including the specific biological effect desired; the air and soil temperature; the quantity and intensity of rainfall before and after treatment; the soil type, pH, fertility and moisture content; the physiological condition and vigor of the target plants; the relative humidity and wind velocity of the air around the crop; the extent and density of the foliar canopy of the target plant; the light quality, intensity and duration each day; and the type and interval of previous and subsequent crop protectant chemical applications. All of these factors may have an influence on the efficacy of chemicals applied as harvest aids.
EXAMPLE 20
To illustrate the effectiveness of the described oxathiazines as crop plants desiccants, a 6000 ppm solution/suspension of active ingredient was made up as described in Example 18. The chemical solutions/suspensions were applied to soybean.sup.(1) and cotton.sup.(2) plants as in Example 19. After 3 weeks in the greenhouse, the plants were scored for leaf desiccation on a 0 to 100 scale, 0 being no damage and 100 being complete kill. A rating system suggested by Frans and Talbert (1977. Research Methods in Weed Science, 2nd edition, Southern Weed Science Society) was used as a guide. The data obtained appear in Table 7.
.sup.(1) Glycine max (L.) Merr. cv. Williams
.sup.(2) Gossypium hirsutum (L.) cv. Stoneville 213
TABLE 7______________________________________FOLIAGE DESICCATION ON COTTON ANDSOYBEAN AT 6000 PPMCompound % desiccationNo. soybean cotton______________________________________ 1 5 35 3 100 100 5 100 100 6 95 100 7 40 0 8 100 100 9 100 10010 98 9811 100 10012 5 5013 0 10014 35 015 85 9516 98 10017 40 1518 98 9819 95 10021 100 9824 100 10026 100 10027 100 10028 100 10029 100 10030 100 10031 100 5032 100 10033 100 10034 65 3035 100 9536 100 4037 95 3538 100 8539 100 10040 90 2541 100 10042 100 9543 85 2044 90 10045 75 6046 95 10047 90 8548 30 1549 30 2050 50 2051 15 8052 80 3054 30 1057 90 558 95 10059 95 060 35 061 80 064 25 065 25 057 90 568 95 10069 45 071 95 9572 85 2573 100 9574 30 075 90 076 55 9077 65 079 65 580 85 581 65 082 100 3083 100 9084 95 10085 80 1586 100 6587 95 1089 95 10090 90 591 95 10092 95 10093 70 1096 95 10097 95 10098 25 0101 75 30103 70 20104 25 15108 55 10110 65 5111 55 0113 95 90114 30 0116 60 0118 20 0120 0 65121 35 5122 80 20124 25 0125 20 5126 85 100128 0 25129 85 100130 100 100131 55 0132 95 100133 95 100134 85 10135 95 100136 95 100137 35 0138 30 100______________________________________
EXAMPLE 21
To further illustrate the effectiveness of the described 3-aryl-5,6-dihydro-1,4,2-oxathizines as plant defoliants, a 6000 ppm weight for volume (w/v) solution/suspension of tested chemical was prepared by dissolving 600 mg chemical in 10 ml suitable organic solvent. The solution was diluted to 100 ml with distilled water containing about 2000 ppm w/v surface active agent (e.g., "Tween 20"). Twenty-five (25) ml of this 6000 ppm solution/suspension were diluted to 100 ml with distilled water containing about 2000 ppm surface active agent, resulting in a 1500 ppm solution/suspension of test chemical. The chemical was applied to cotton plants (Gossypium hirsutum L. "Stoneville 213") by immersion of the lower leaves. At the time of treatment, the cotton plants had 2 to 4 true leaves. After treatment, the plants were returned to the greenhouse for about two weeks, at which time the plants were evaluated for defoliation of the treated leaves. The scoring system used: 1=5-25% defoliation, 2= 26-50%, 3=51-70%, 4=71-85%, 5=86-100%. The results appear in TABLE 8.
TABLE 8______________________________________COTTON DEFOLIATION AT 1500 PPMCompound DefoliationNo. Score______________________________________ 1 5 3 5 5 5 6 5 9 510 511 512 515 516 217 518 520 523 224 526 527 528 531 133 335 536 537 438 539 241 542 244 346 551 352 555 160 563 364 565 566 167 468 569 170 171 272 373 474 175 276 577 278 182 283 284 586 187 188 189 591 592 594 195 296 597 5100 1105 1106 1108 1109 1110 1113 1114 1115 4116 4117 2118 5120 5121 2122 5124 2125 1126 5128 5129 5130 5131 2132 5133 5134 5136 5135 5137 2138 5______________________________________
Similar defoliating activity is observed with compounds of this invention wherein R is trichlorophenyl, R.sup.1 is n-butyl, t-butyl or benzyl and n is 0, 1 or 2.
In fungicidal applications, the chemicals may be applied directly to plants (i.e. seeds, foliage) or to soil in which plants are growing or to be grown, to protect against the harmful effects of pathogenic fungi. For example, the chemical may be applied to seeds by tumbling the chemical with the seeds, either alone or in admixture with a powdered solid carrier. Typical powdered solid carriers are the various mineral silicates, e.g., mica, talc, pyrophyllite, and clays. The chemical may also be applied to the seeds in admixture with a conventional surface-active wetting agent, with or without additional powdered solid carrier, as by first wetting the mixture with a small amount of water and then tumbling the seeds in the slurry. The surface-active wetting agents that may be used with the fungicide may be any of the conventional anionic, non-ionic, or cationic surface-active agents. Such surface-active agents are well known and reference is made to U.S. Pat. No. 2,546,724, columns 3 and 4, for detailed examples of the same. As a seed protectant, the amount of the chemical coated on the seeds will be 1/4 to 12 oz. (7-350 g) per hundred lbs. (45.5 kg) of the seed. As a soil treatment for fungi, the chemical may be applied: (a) as a dust in admixture with sand or soil a powdered solid carrier such as a mineral silicate, with or without an additional surface-active wetting agent, to the furrows simultaneously with the planting of the seeds; or (b) an aqueous spray, if desired including a surface-active or dispersing agent, or a surface-active or dispersing agent and a powdered solid carrier, to the seed rows before, or with, or after planting the seeds. As a soil treatment, the amount of the chemical applied to the seed rows will be from 0.1 to 10 pounds per acre (0.112 to 11.2 kg/ha) based on rows 2" (5 cm) wide and 2" (5 cm) deep a distance of 40" (102 cm) apart. Also, as a soil treatment, the chemical may be applied broadcast using a similar dust or aqueous spray with an application rate of 1.0 to 100 pounds per acre (1.12 to 112 kg/ha). As a foliage treatment, the chemical may be applied to growing plants at a rate of 1/4 to 10 pounds per acre (0.28 to 11.2 kg/ha). Such application is generally as an aqueous spray which also contains a surface-active or dispersing agent, with or without a powdered solid carrier or hydrocarbon solvent. These sprays usually are repeated at time intervals ranging from three days to two weeks during the growing season. Typical formulations are as follows (all percentages are by weight):
______________________________________(a) Emulsifiable concentrate:48.1% Active Ingredient11.1% Surfactant (e.g., polyoxyethylene sorbitan monooleate)40.8% Xylene100.0% Total(b) Wettable powder:75.0% Active Ingredient2.0% Triton (trademark) X-1202.0% Daxad (trademark) - 1121.0% Dixie clay100.0% Total______________________________________
Triton X-120 is an alkylaryl polyether alcohol (9-10 moles polyethylene oxide) in dry powdered form (40% active on an insoluble carrier). The active ingredient in Triton X-120 is Triton X-100, which is a liquid nonionic surfactant (isooctyl-phenylpolyethoxyethanol, obtained by condensing the alkylphenylphenol with ethylene oxide). Daxad-11 is polymerized sodium salt of alkylnaphthalene sulfonic acid (more particularly, the sodium salts of binaphthyl/methane sulfonic acids obtained from naphthalene, sulfuric acid and formaldehyde, according to U.S. Pat. No. 1,336,759, Schmidt, Apr. 13, 1920).
EXAMPLE 22
Foliage Spray Treatment for Control of Established Bean Rust disease caused by the fungus (Uromyces phaseoli)
Although many chemicals will serve to protect plants from disease, it is often desirable to draw upon chemicals which have therapeutic properties to arrest the development of disease that has already become established. This example illustrates such properties.
Two hundred (200) milligrams of chemical were dissolved in 20 ml of acetone and 60 mg of a surfactant such as Triton X-100. This preparation was diluted with 80 ml distilled water giving a chemical suspension of 2000 ppm. Further serial dilutions were prepared from this as desired. The chemical suspensions were sprayed on duplicate pots, each containing two snapbean plants which had, 48 hours prior to this, been inoculated with the bean rust fungus Uromyces phaseoli typica Arth. At the time of the chemical spray the bean plants had just begun to expand their first trifoliolate leaves. The test plants were then placed in a chamber for 24 hours at 75.degree. F. (24.degree. C.) and 100% relative humidity. After this time the plants were returned to the greenhouse. About 10 days later the plants were scored for disease control, with the results shown in TABLE 9.
TABLE 9______________________________________Bean Rust Disease Control by Foliar Application at 1000 ppm % DISEASECOMPOUND CONTROL______________________________________29 9528 90* 5 95______________________________________
EXAMPLE 23
Foliar Spray for Protecting Tomato Plants from infection by the Early Blight Fungus, Alternaria solani
Test procedure
One gram of the chemical to be tested was ground with three ml of acetone and 50 mg of a non-ionic surface-active agent (Triton X-100). The acetone and surface-active agent are known to be inactive in this biological test. The mixture was diluted with water, giving suspensions containing 500 and 2000 ppm of the chemical. These suspensions were sprayed on duplicate six-inch (ca. 15 cm) tomato plants (variety Clark's Early Special) using a gun-type sprayer. Twenty-four hours later the treated and untreated check plants were inoculated with a suspension of Alternaria solani spores by means of a 20 second spray from an atomizer sprayer (delivery rate 1 ml per second). The plants were then kept overnight in a controlled chamber at a temperature of 75.degree. F. (24.degree. C.) and 100% relative humidity. In the morning the plants were transferred to the greenhouse. Three days later the disease was scored by comparing the number of disease lesions of the treated plants with the untreated control. The formula used to determine percent control is: ##EQU1##
The results are shown in TABLE 10.
TABLE 10______________________________________Control of Tomato Early Blight Diseaseby Foliar Application at 1000 ppm. % DISEASECOMPOUND CONTROL______________________________________4 92______________________________________
EXAMPLE 24
Foliar Spray for protecting plants from infection by the Rice Blast fungus, Piricularia oryza
Test procedure
The chemical suspensions were prepared in manner described in Example 23. The suspensions were sprayed on duplicate pots of clustered 7-day old barley plants (variety Herta) using a gun-type sprayer. The plants were then placed in a greenhouse together with untreated check plants and allowed to dry. All test plants were inoculated with the fungus by spraying with a suspension of Piricularia oryzae spores (20,000-40,000 spores/ml) to which a standard wetting agent has been added (Tween 20, 6 drops/300 ml). After inoculation the plants were kept in a temperature-humidity control chamber for 24-48 hours at 70.degree. F. (21.degree. C.) to allow infection. Plants were then removed and placed in a 70.degree. F. (21.degree. C.) greenhouse to allow disease development. After 5 to 7 days, blast lesions appeared on the leaves. Disease control was evaluated by either counting lesions if infection was moderate or evaluating by a disease rating scale of 0-6 with 6 being severe disease. Percent control was computed by comparing the treatment scores with that of the untreated control (TABLE 11).
TABLE 11______________________________________Control of Piricularia Blast DiseaseOn Barley by Foliar Application % DISEASECOMPOUND PPM CONTROL______________________________________32 1000 87 4 500 8421 1000 8365 500 8577 500 8591 500 100______________________________________
EXAMPLE 25
Antifungal activity as demonstrated by laboratory tests on fungus cultures
The chemicals of the invention were dissolved in acetone, and applied at 500 ppm to 13 mm antibiotic testing discs by dipping the discs in the test solutions. After drying, the treated discs were placed on an agar plate (4 per plate), then 7 mm plugs of mycelium of various fungi were placed on the center of the discs in such fashion that the fungus mat was in direct contact with the treated disc. The fungitoxic activity of the chemicals was measured by comparing growth (colony radius) of the fungus on the treated discs with that on untreated controls. Colony radius was measured when untreated controls reaches 80-90% of the area available for growth on the plates. The fungi tested were Alternaria solani (A), Fusarium oxysporum (F), Pythium sp. (P) and Sclerotium rolfsii (S). The results are shown in TABLE 12.
TABLE 12______________________________________ % INHIBITION @ 500 ppmCOMPOUND A F P S______________________________________ 6 65 -- 90 -- 8 50 -- 100 90 9 50 -- 100 --35 -- -- 60 9047 70 -- -- --48 70 -- -- --78 10 -- -- 10029 75 70 100 3032 30 70 100 5541 80 -- 100 8042 80 -- 100 8036 30 55 100 7028 85 70 100 40 5 100 95 80 10019 95 90 100 9546 95 95 100 8015 75 70 100 4552 100 -- 100 6521 65 45 95 5533 100 100 100 9538 75 65 100 10038 75 -- 100 10053 100 -- 100 6582 75 -- 100 6584 80 -- 100 6586 100 -- 100 8591 65 -- 90 5543 -- -- 100 55 4 100 20 50 --59 80 -- -- 40 7 20 -- 100 5058 -- -- 90 4517 80 70 30 3024 95 90 100 9521 45 5 85 2544 -- 100 100 6053 90 -- 60 5057 65 -- 100 6065 95 -- 75 8577 75 -- 80 6081 60 -- 70 7585 90 -- 100 65______________________________________
EXAMPLE 26
Foliar Spray for protecting plants from infection by the peanut leafspot fungus, Cercospora arachidicola.
TEST PROCEDURE
The chemical suspensions were prepared in a manner described in Example 23. The suspensions were sprayed on duplicate pots of clustered one-month old peanut plants (variety Florrunner), using a gun-type sprayer. After the plants were dried, they were inoculated with the fungus by spraying with a suspension of Cercospora arachidicola spores (20,000 spores/ml) to which a standard wetting agent had been added (Tween 20, 6 drops/300 ml). Plants were placed in temperature-humidity controlled chamber for 24-48 hours at 70.degree. F. (21.degree. C.) to allow infection to be initiated. Plants were then removed from the chamber and transferred to a 70.degree. F. (21.degree. C.) greenhouse to allow disease development. After about 21 days, symptoms had developed on the leaflets. Disease control was evaluated by counting lesions if infection was moderate or evaluating by a disease rating scale of 0-6, with 6 being severe disease. Percent control was computed by comparing the treatment scores with that of the untreated control. The results are shown in TABLE 13.
TABLE 13______________________________________Control of Cercospora Leafspot Disease ofPeanuts by Foliar Application % DISEASECOMPOUND PPM CONTROL______________________________________65 1000 95 500 9077 1000 93 500 9584 1000 100 500 10067 1000 80 500 4568 1000 85 500 8072 1000 78 500 7873 1000 80 500 7575 1000 50 500 5082 1000 90 5000 8083 1000 90 500 9590 1000 96 500 9295 1000 55 5000 5597 1000 80 500 90______________________________________

3-Aryl-5,6-dihydro-1,4,2-oxathiazines and their oxides

Information

Patent Number

Date Filed

Date Issued

Inventors

Original Assignees

Examiners

Agents

CPC

US Classifications

Field of Search

US

International Classifications

Abstract

Description

Claims

Parent Case Info

Foreign Referenced Citations (1)

Continuation in Parts (1)