The invention relates to the stabilization of edible organic substances subject to deterioration by oxidation. Antioxidants are of great importance in edible fats and fatty oils such as fatty acid glycerides, and in foods made with edible fats and fatty oils. The antioxidants are used to prevent or alleviate oxidative rancidity which causes undesirable flavors and odors, destroys fat-soluble vitamins and essential fatty acids, and produces toxicological effects. A food antioxidant should not impart undesirable characteristics, such as unpleasant odor or discoloration and advantageously has good carry-through which is the ability to survive baking or frying operations and provide improved keeping quality in food prepared from the stabilized edible organic substances.
The art shows many methods of inhibiting lipid oxidation by adding fat-soluble antioxidants to the substrate. The art does not show the stabilization of fats, oils, fatty foods and ingredients of foods employing one or more antioxidants selected from the group consisting of 3-arylbenzofuranones, long chain N,N-dialkylhydroxylamines, substituted hydroxylamines, nitrones, and amine oxides as defined hereinafter.
Phenols are commonly employed as antioxidants to stabilize organic materials and substituted phenols have been found to have improved antioxidant effectiveness since the efficiency of the phenol group in terminating oxidation is affected by the nature of the ring substituents. Some known phenolic antioxidants are not suitable for use in food because they are toxic to higher forms of animal life. For example, p-aminophenol is highly toxic and is a skin irritant.
Several phenolics have been used as antioxidants in foodstuffs, including butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA). Even these antioxidants are now being examined by regulatory agencies and consumer activists and these developments have urged the need to exploit new sources of antioxidants for use in food applications. Also propyl gallate (PG), t-butylhydroxyquinone (TBHQ), iso-ascorbic acid, chloro-iso-ascorbic acid and ascorbyl palmitate have been permitted for use in food applications.
Young, U.S. Pat. No. 2,654,722, discloses the use of acyl-p-aminophenols to stabilize solid organic materials, such as synthetic rubbers, which tend to deteriorate due to oxidation. The acyl substitutent in these antioxidants has at least three carbon atoms and can be employed as food stabilizers.
U.S. Pat. No. 3,492,349 to Doyle and Baxter discloses di-lower alkyl-alkoxy- and hydroxyacetanilides. The patent teaches that these compounds have analgesic and antipyretic properties and low toxicity. The compound of this patent of the formula
wherein R3 is a hydrocarbon group may not have antioxidant activity since the effectiveness of p-aminophenols and other phenolics generally depends upon the presence of a free hydroxyl group, and the ethers and esters of these phenols generally have no significant effect.
U.S. Pat. No. 4,038,434 to Young discloses that certain N-acyl-2,6-dialkyl-p-aminophenols are highly effective antioxidants for use with edible organic substances.
U.S. Pat. No. 4,094,999 to Cohen and O'Connell discloses a food composition stabilized by the presence therein of a small proportion of a dialkyl pentaerythritol diphosphite.
U.S. Pat. No. 4,363,910 to Ambrus, Szabolesi and Hutas disclose the use of 2,2-dimethyl-1,2-dihydroquinoline derivatives useful as antioxidants to stabilize animal feedstuffs.
U.S. Pat. No. 5,084,289 to Shin, Han and Yi discloses a method for inhibiting the oxidation of edible oils and fats by forming a reverse miscelle by admixing a mixture of an aqueous solution containing tocopherol and ascorbic acid with a surfactant and said oils or fats.
U.S. Pat. No. 3,778,464 to Klemchuk discloses substituted hydroxylamine antioxidants of the formula R7R8NOH wherein R7 or R8 is alkyl containing from 1 to 3 carbon atoms, benzyl, chlorobenzyl, nitrobenzyl, benzhydryl or triephenylmethyl with the proviso that only one of R7 or R8 is alkyl and that R8 is hydrogen when R7 is benzhydryl or triphenylmethyl, or R7 and R8 taken together with the nitrogen atom form a heterocyclic group such as morpholino, piperidino or piperazino. The compounds are stated to be useful for organic substances including fats and oils of animal fats and foods made therewith or therein.
Other antioxidants for food include those disclosed in U.S. Pat. No. 5,527,552 to Todd, Jr.—green tea catechins; U.S. Pat. No. 4,925,681 to Mai, Chambers and McDonald—extracts from black tea.
It is an object of the invention to provide food compositions having improved stability and containing antioxidant compositions which include one or more of the antioxidants disclosed, herein.
It is a related object of this invention to provide a method of stabilizing food products through the addition thereto of antioxidant compositions which include one or more of the antioxidants of the present invention.
It is still another object of this invention to provide edible fat and oil compositions having improved stability and containing antioxidant compositions which include one or more of the antioxidants disclosed herein.
It is a still further object of this invention to provide a method of stabilizing edible fat and oil compositions through the addition thereto of antioxidant compositions which include one or more of the antioxidants of the present invention.
It is has now been found that a combination of one or more compounds selected from the group consisting of 3-arylbenzofuranones, long chain N,N-dialkylhydroxylamines, substituted hydroxylamines, nitrones, and amine oxides as defined hereinafter are highly effective antioxidants for use with edible organic substances subject to deterioration by oxidation.
Edible organic substances that may be stabilized against oxidation include hydrocarbon-containing substances that are suitable for human or animal consumption, for example, frying oils and fats, potato flakes, bakery products, meat emulsions, precooked cereals, instant noodles, soybean milk, chicken products, emulsion products such as sausage, mayonnaise and margarine, frozen fish, frozen pizza, cheese and animal foods.
The antioxidants of this invention are extremely useful in the stabilization of fats, fatty alcohols, fatty acids, esters of fatty acids and fatty oils which may be essentially solid or liquid at room temperature, and may be hydrogenated or unhydrogenated as well as various foods containing or prepared in such products. The oils or fats may be naturally-occurring, such as animal or vegetable fats, or synthetic materials. Exemplary materials are tallow, lard, peanut oil, corn oil, cottonseed oil, olive oil, safflower oil, soybean oil, coconut oil, shortening, cooking oils, salad oils and dressings, mayonnaise, margarine and the like. The fatty acid portion of such materials generally has at least about 12 carbon atoms, say up to about 24 or more carbon atoms per ester site, and the ester portions are frequently glycerides, although the materials may be other types of esters of various mono and polyhydroxy alkyl alcohols. Generally, the ester portions of the molecule have less than about 12 carbon atoms, preferably less than about 6 carbon atoms, e.g. glycerides or other lower alkyl esters.
The 3-arylbenzofuranones antioxidants of the present invention are for example those disclosed in U.S. Pat. Nos. 4,325,863; 4,388,244; 5,175,312; 5,252,643; 5,216,052; 5,369,159; 5,488,117; 5,356,966; 5,367,008; 5,428,162; 5,428,177; and 5,516,920; which are hereby incorporated by reference.
Particularly suitable 3-arylbenzofuranones in the present invention are compounds of the formula I
in which, if n is 1,
R1 is unsubstituted or C1-C4alkyl-, C1-C4alkoxy-, C1-C4alkylthio-, hydroxyl-, halo-, amino-, C1-C4alkylamino-, phenylamino- or di(C1-C4alkyl)amino-substituted naphthyl, phenanthryl, anthryl, 5,6,7,8-tetrahydro-2-naphthyl, 5,6,7,8-tetrahydro-1-naphthyl, thienyl, benzo[b]thienyl, naphtho[2,3-b]thienyl, thianthrenyl, dibenzofuryl, chromenyl, xanthenyl, phenoxathiinyl, pyrrolyl, imidazolyl, pyrazolyl, pyrazinyl, pyrimidinyl, pyridazinyl, indolizinyl, isoindolyl, indolyl, indazolyl, purinyl, quinolizinyl, isoquinolyl, quinolyl, phthalazinyl, naphthyridinyl, quinoxalinyl, quinazolinyl, cinnolinyl, pteridinyl, carbazolyl, β-carbolinyl, phenanthridinyl, acridinyl, perimidinyl, phenanthrolinyl, phenazinyl, isothiazolyl, phenothiazinyl, isoxazolyl, furazanyl, biphenyl, terphenyl, fluorenyl or phenoxazinyl, or R1 is a radical of the formula II
and
if n is 2,
R1 is unsubstituted or C1-C4alkyl- or hydroxy-substituted phenylene or naphthylene; or is -R12-X-R13-,
R2, R3, R4 and R5 independently of one another are hydrogen, chlorine, hydroxyl, C1-C25alkyl, C7-C9phenylalkyl, unsubstituted or C1-C4alkyl-substituted phenyl; unsubstituted or C1-C4alkyl-substituted C5-C8cycloalkyl; C1-C18alkoxy, C1-C18alkylthio, C1-C4alkylamino, di(C1-C4alkyl)amino, C1-C25alkanoyloxy, C1-C25alkanoylamino, C3-C25alkenoyloxy, C3-C25alkanoyloxy which is interrupted by oxygen, sulfur or
C6-C9cycloalkyl-carbonyloxy, benzoyloxy or C1-C12alkyl-substituted benzoyloxy; or else the radicals R2 and R3 or the radicals R3 and R4 or the radicals R4 and R5, together with the carbon atoms to which they are attached, form a benzo ring, R4 is additionally —(CH2)p—COR15 or —(CH2)qOH or, if R3, R5 and R6 are hydrogen, R4 is additionally a radical of the formula III
in which R1 is defined as indicated above for n=1,
R6 is hydrogen or a radical of the formula IV
where R4 is not a radical of the formula III and R1 is defined as indicated above for n=1, R7, R8, R9, R10 and R11 independently of one another are hydrogen, halogen, hydroxyl, C1-C25alkyl, C2-C25alkyl interrupted by oxygen, sulfur or
C1-C25alkoxy, C2-C25alkoxy interrupted by oxygen, sulfur or
C1-C25alkylthio, C3-C25alkenyl, C3-C25alkenyloxy, C3-C25alkynyl, C3-C25alkynyloxy, C7-C9phenylalkyl, C7-C9phenylalkoxy, unsubstituted or C1-C4alkyl-substituted phenyl; unsubstituted or C1-C4alkyl-substituted phenoxy; unsubstituted or C1-C4alkyl-substituted C5-C8cycloalkyl; unsubstituted or C1-C4alkyl-substituted C5-C8cycloalkoxy; C1-C4alkylamino, di(C1-C4alkyl)amino, C1-C25alkanoyl, C3-C25alkanoyl interrupted by oxygen, sulfur or
C1-C25alkanoyloxy, C3-C25alkanoyloxy interrupted by oxygen, sulfur or
C1-C25alkanoylamino, C3-C25alkenoyl, C3-C25alkenoyl interrupted by oxygen, sulfur or
C3-C25alkenoyloxy, C3-C25alkenoyloxy interrupted by oxygen, sulfur or
C6-C9cycloalkylcarbonyl, C6-C9cycloalkylcarbonyloxy, benzoyl or C1-C12alkyl-substituted benzoyl; benzoyloxy or C1-C12alkyl-substituted benzoyloxy;
else, in formula II, the radicals R7 and R8 or the radicals R8 and R11, together with the carbon atoms to which they are attached, form a benzo ring,
R12 and R13 independently of one another are unsubstituted or C1-C4alkyl-substituted phenylene or naphthylene,
R14 is hydrogen or C1-C8alkyl,
R15 is hydroxyl,
C1-C18alkoxy or
R16 and R17 independently of one another are hydrogen, CF3, C1-C12alkyl or phenyl, or R16 and R17, together with the C atom to which they are attached, form a C5-C8cycloalkylidene ring which is unsubstituted or substituted from 1 to 3 times by C1-C4alkyl;
R18 and R19 independently of one another are hydrogen, C1-C4alkyl or phenyl,
R20 is hydrogen or C1-C4alkyl,
R21 is hydrogen, unsubstituted or C1-C4alkyl-substituted phenyl; C1-C25alkyl, C2-C25alkyl interrupted by oxygen, sulfur or
C7-C9phenylalkyl which is unsubstituted or substituted on the phenyl radical from 1 to 3 times by C1-C4alkyl; C7-C25phenylalkyl which is unsubstituted or substituted on the phenyl radical from 1 to 3 times by C1-C4alkyl and interrupted by oxygen, sulfur or
or else the radicals R20 and R21, together with the carbon atoms to which they are attached, form a C5-C12cycloalkylene ring which is unsubstituted or substituted from 1 to 3 times by C1-C4alkyl;
R22 is hydrogen or C1-C4alkyl,
R23 is hydrogen, C1-C25alkanoyl, C3-C25alkenoyl, C3-C25alkanoyl interrupted by oxygen, sulfur or
C2-C25alkanoyl substituted by a di(C1-C6alkyl)phosphonate group; C6-C9cycloalkylcarbonyl, thenoyl, furoyl, benzoyl or C1-C12alkyl-substituted benzoyl;
R24 and R25 independently of one another are hydrogen or C1-C18alkyl,
R26 is hydrogen or C1-C8alkyl,
R27 is a direct bond, C1-C18alkylene, C2-C18alkylene interrupted by oxygen, sulfur or
C2-C18alkenylene, C2-C20alkylidene, C7-C20phenylalkylidene, C5-C8cycloalkylene, C7-C8bicycloalkylene, unsubstituted or C1-C4alkyl-substituted phenylene, or
or
R28 is hydroxyl,
C1-C18alkoxy or
R29 is oxygen, —NH— or
R30 is C1-C18alkyl or phenyl,
R31 is hydrogen or C1-C18alkyl,
M is an r-valent metal cation,
X is a direct bond, oxygen, sulfur or —NR31—,
n is 1 or 2,
p is 0, 1 or 2,
q is 1, 2, 3, 4, 5 or 6,
r is 1, 2 or 3, and
s is 0, 1 or 2.
Unsubstituted or C1-C4alkyl-, C1-C4alkoxy-, C1-C4alkylthio-, hydroxyl-, halo-, amino-, C1-C4alkylamino-, phenylamino- or di(C1-C4alkyl)amino-substituted naphthyl, phenanthryl, anthryl, 5,6,7,8-tetrahydro-2-naphthyl, 5,6,7,8-tetrahydro-1-naphthyl, thienyl, benzo[b]thienyl, naphtho[2,3-b]thienyl, thianthrenyl, dibenzofuryl, chromenyl, xanthenyl, phenoxathiinyl, pyrrolyl, imidazolyl, pyrazolyl, pyrazinyl, pyrimidinyl, pyridazinyl, indolizinyl, isoindolyl, indolyl, indazolyl, purinyl, quinolizinyl, isoquinolyl, quinolyl, phthalazinyl, naphthyridinyl, quinoxalinyl, quinazolinyl, cinnolinyl, pteridinyl, carbazolyl, β-carbolinyl, phenanthridinyl, acridinyl, perimidinyl, phenanthrolinyl, phenazinyl, isothiazolyl, phenothiazinyl, isoxazolyl, furazanyl, biphenyl, terphenyl, fluorenyl or phenoxazinyl is, for example, 1-naphthyl, 2-naphthyl, 1-phenylamino-4-naphthyl, 1-methylnaphthyl, 2-methylnaphthyl, 1-methoxy-2-naphthyl, 2-methoxy-1-naphthyl, 1-dimethylamino-2-naphthyl, 1,2-dimethyl-4-naphthyl, 1,2-dimethyl-6-naphthyl, 1,2-dimethyl-7-naphthyl, 1,3-dimethyl-6-naphthyl, 1,4-dimethyl-6-naphthyl, 1,5-dimethyl-2-naphthyl, 1,6-dimethyl-2-naphthyl, 1-hydroxy-2-naphthyl, 2-hydroxy-1-naphthyl, 1,4-dihydroxy-2-naphthyl, 7-phenanthryl, 1-anthryl, 2-anthryl, 9-anthryl, 3-benzo[b]thienyl, 5-benzo[b]thienyl, 2-benzo[b]thienyl, 4-dibenzofuryl, 4,7-dibenzofuryl, 4-methyl-7-dibenzofuryl, 2-xanthenyl, 8-methyl-2-xanthenyl, 3-xanthenyl, 2-phenoxathiinyl, 2,7-phenoxathiinyl, 2-pyrrolyl, 3-pyrrolyl, 5-methyl-3-pyrrolyl, 2-imidazolyl, 4-imidazolyl, 5-imidazolyl, 2-methyl-4-imidazolyl, 2-ethyl-4-imidazolyl, 2-ethyl-5-imidazolyl, 3-pyrazolyl, 1-methyl-3-pyrazolyl, 1-propyl-4-pyrazolyl, 2-pyrazinyl, 5,6-dimethyl-2-pyrazinyl, 2-indolizinyl, 2-methyl-3-isoindolyl, 2-methyl-1-isoindolyl, 1-methyl-2-indolyl, 1-methyl-3-indolyl, 1,5-dimethyl-2-indolyl, 1-methyl-3-indazolyl, 2,7-dimethyl-8-purinyl, 2-methoxy-7-methyl-8-purinyl, 2-quinolizinyl, 3-isoquinolyl, 6-isoquinolyl, 7-isoquinolyl, isoquinolyl, 3-methoxy-6-isoquinolyl, 2-quinolyl, 6-quinolyl, 7-quinolyl, 2-methoxy-3-quinolyl, 2-methoxy-6-quinolyl, 6-phthalazinyl, 7-phthalazinyl, 1-methoxy-6-phthalazinyl, 1,4-dimethoxy-6-phthalazinyl, 1,8-naphthyridin-2-yl, 2-quinoxalinyl, 6-quinoxalinyl, 2,3-dimethyl-6-quinoxalinyl, 2,3-dimethoxy-6-quinoxalinyl, 2-quinazolinyl, 7-quinazolinyl, 2-dimethylamino-6-quinazolinyl, 3-cinnolinyl, 6-cinnolinyl, 7-cinnolinyl, 3-methoxy-7-cinnolinyl, 2-pteridinyl, 6-pteridinyl, 7-pteridinyl, 6,7-dimethoxy-2-pteridinyl, 2-carbazolyl, 3-carbazolyl, 9-methyl-2-carbazolyl, 9-methyl-3-carbazolyl, β-carbolin-3-yl, 1-methyl-β-carbolin-3-yl, 1-methyl-β-carbolin-6-yl, 3-phenanthridinyl, 2-acridinyl, 3-acridinyl, 2-perimidinyl, 1-methyl-5-perimidinyl, 5-phenanthrolinyl, 6-phenanthrolinyl, 1-phenazinyl, 2-phenazinyl, 3-isothiazolyl, 4-isothiazolyl, 5-isothiazolyl, 2-phenothiazinyl, 3-phenothiazinyl, 10-methyl-3-phenothiazinyl, 3-isoxazolyl, 4-isoxazolyl, 5-isoxazolyl, 4-methyl-3-furazanyl, 2-phenoxazinyl or 10-methyl-2-phenoxazinyl.
Particular preference is given to unsubstituted or C1-C4alkyl-, C1-C4alkoxy-, C1-C4alkylthio-, hydroxyl-, phenylamino- or di(C1-C4alkyl)amino-substituted naphthyl, phenanthryl, anthryl, 5,6,7,8-tetrahydro-2-naphthyl, 5,6,7,8-tetrahydro-1-naphthyl, thienyl, benzo[b]thienyl, naphtho[2,3-b]thienyl, thianthrenyl, dibenzofuryl, chromenyl, xanthenyl, phenoxathiinyl, pyrrolyl, isoindolyl, indolyl, phenothiazinyl, biphenyl, terphenyl, fluorenyl or phenoxazinyl such as, for example, 1-naphthyl, 2-naphthyl, 1-phenylamino-4-naphthyl, 1-methylnaphthyl, 2-methyl-naphthyl, 1-methoxy-2-naphthyl, 2-methoxy-1-naphthyl, 1-dimethylamino-2-naphthyl, 1,2-dimethyl-4-naphthyl, 1,2-dimethyl-6-naphthyl, 1,2-dimethyl-7-naphthyl, 1,3-dimethyl-6-naphthyl, 1,4-dimethyl-6-naphthyl, 1,5-dimethyl-2-naphthyl, 1,6-dimethyl-2-naphthyl, 1-hydroxy-2-naphthyl, 2-hydroxy-1-naphthyl, 1,4-dihydroxy-2-naphthyl, 7-phenanthryl, 1-anthryl, 2-anthryl, 9-anthryl, 3-benzo[b]thienyl, 5-benzo[b]thienyl, 2-benzo[b]thienyl, 4-dibenzofuryl, 4,7-dibenzofuryl, 4-methyl-7-dibenzofuryl, 2-xanthenyl, 8-methyl-2-xanthenyl, 3-xanthenyl, 2-pyrrolyl, 3-pyrrolyl, 2-phenothiazinyl, 3-phenothiazinyl, 10-methyl-3-phenothiazinyl.
Halogen (halo) is, for example, chlorine, bromine or iodine. Preference is given to chlorine.
Alkanoyl having up to 25 carbon atoms is a branched or unbranched radical such as, for example, formyl, acetyl, propionyl, butanoyl, pentanoyl, hexanoyl, heptanoyl, octanoyl, nonanoyl, decanoyl, undecanoyl, dodecanoyl, tridecanoyl, tetradecanoyl, pentadecanoyl, hexadecanoyl, heptadecanoyl, octadecanoyl, eicosanoyl or docosanoyl. Preference is given to alkanoyl having 2 to 18, especially 2 to 12, for example 2 to 6 carbon atoms. Particular preference is given to acetyl.
C2-C25alkanoyl substituted by a di(C1-C6alkyl)phosphonate group is, for example, (CH3CH2O)2POCH2CO—, (CH3O)2POCH2CO—, (CH3CH2CH2CH2O)2POCH2CO—, (CH3CH2O)2POCH2CH2CO—, (CH3O)2POCH2CH2CO—, (CH3CH2CH2CH2O)2POCH2CH2CO—, (CH3CH2O)2PO(CH2)4CO—, (CH3CH2O)2PO(CH2)8CO— or (CH3CH2O)2PO(CH2)17CO—.
Alkanoyloxy having up to 25 carbon atoms is a branched or unbranched radical such as, for example, formyloxy, acetoxy, propionyloxy, butanoyloxy, pentanoyloxy, hexanoyloxy, heptanoyloxy, octanoyloxy, nonanoyloxy, decanoyloxy, undecanoyloxy, dodecanoyloxy, tridecanoyloxy, tetradecanoyloxy, pentadecanoyloxy, hexadecanoyloxy, heptadecanoyloxy, octadecanoyloxy, eicosanoyloxy or docosanoyloxy. Preference is given to alkanoyloxy having 2 to 18, especially 2 to 12, for example 2 to 6 carbon atoms. Particular preference is given to acetoxy.
Alkenoyl having 3 to 25 carbon atoms is a branched or unbranched radical such as, for example, propenoyl, 2-butenoyl, 3-butenoyl, isobutenoyl, n-2,4-pentadienoyl, 3-methyl-2-butenoyl, n-2-octenoyl, n-2-dodecenoyl, iso-dodecenoyl, oleoyl, n-2-octadecenoyl or n-4-octadecenoyl. Preference is given to alkenoyl having 3 to 18, especially 3 to 12, for example 3 to 6, in particular 3 to 4 carbon atoms.
C3-C25alkenoyl interrupted by oxygen, sulfur or
is, for example, CH3OCH2CH2CH═CHCO— or CH3OCH2CH2OCH═CHCO—.
Alkenoyloxy having 3 to 25 carbon atoms is a branched or unbranched radical such as, for example, propenoyloxy, 2-butenoyloxy, 3-butenoyloxy, isobutenoyloxy, n-2,4-pentadienoyloxy, 3-methyl-2-butenoyloxy, n-2-octenoyloxy, n-2-dodecenoyloxy, iso-dodecenoyloxy, oleoyloxy, n-2-octadecenoyloxy or n-4-octadecenoyloxy. Preference is given to alkenoyloxy having 3 to 18, especially 3 to 12, for example 3 to 6, in particular 3 to 4 carbon atoms.
C3-C25alkenoyloxy interrupted by oxygen, sulfur or
is, for example, CH3OCH2CH2CH═CHCOO— or CH3OCH2CH2OCH═CHCOO—.
C3-C25alkanoyl interrupted by oxygen, sulfur or
is, for example, CH3—O—CH2CO—CH3—S—CH2CO—, CH3—NH—CH2CO—, CH3—N(CH3)—CH2CO—, CH3—O—CH2CH2—O—CH2CO—, CH3—(O—CH2CH2—)2O—CH2CO—, CH3—(O—CH2CH2—)3O—CH2CO— or CH3—(O—CH2CH2—)4O—CH2CO—.
C3-C25alkanoyloxy interrupted by oxygen, sulfur or
is, for example, CH3—O—CH2COO—, CH3—S—CH2COO—, CH3—NH—CH2COO—, CH3—N(CH3)—CH2COO—, CH3—O—CH2CH2—O—CH2COO—, CH3—(O—CH2CH2—)2O—CH2COO—, CH3—(O—CH2CH2—)3O—CH2COO— or CH3—(O—CH2CH2—)4O—CH2COO—.
C6-C9cycloalkylcarbonyl is, for example, cyclopentylcarbonyl, cyclohexylcarbonyl, cycloheptylcarbonyl or cyclooctylcarbonyl. Cyclohexylcarbonyl is preferred.
C6-C9cycloalkylcarbonyloxy is, for example, cyclopentylcarbonyloxy, cyclohexylcarbonyloxy, cycloheptylcarbonyloxy or cyclooctylcarbonyloxy. Cyclohexylcarbonyloxy is preferred.
C1-C12alkyl-substituted benzoyl, which preferably carries 1 to 3, especially 1 or 2 alkyl groups, is, for example, o-, m- or p-methylbenzoyl, 2,3-dimethylbenzoyl, 2,4-dimethylbenzoyl, 2,5-dimethylbenzoyl, 2,6-dimethylbenzoyl, 3,4-dimethylbenzoyl, 3,5-dimethylbenzoyl, 2-methyl-6-ethylbenzoyl, 4-tert-butylbenzoyl, 2-ethylbenzoyl, 2,4,6-trimethylbenzoyl, 2,6-dimethyl-4-tert-butylbenzoyl or 3,5-di-tert-butylbenzoyl. Preferred substituents are C1-C8alkyl, especially C1-C4alkyl.
C1-C12alkyl-substituted benzoyloxy, which preferably carries 1 to 3, especially 1 or 2 alkyl groups, is, for example, o-, m- or p-methylbenzoyloxy, 2,3-dimethylbenzoyloxy, 2,4-dimethylbenzoyloxy, 2,5-dimethylbenzoyloxy, 2,6-dimethylbenzoyloxy, 3,4-dimethylbenzoyloxy, 3,5-dimethylbenzoyloxy, 2-methyl-6-ethylbenzoyloxy, 4-tert-butylbenzoyloxy, 2-ethyl-benzoyloxy, 2,4,6-trimethylbenzoyloxy, 2,6-dimethyl-4-tert-butylbenzoyloxy or 3,5-di-tert-butylbenzoyloxy. Preferred substituents are C1-C8alkyl, especially C1-C4alkyl.
Alkyl having up to 25 carbon atoms is a branched or unbranched radical such as, for example, methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, 2-ethylbutyl, n-pentyl, isopentyl, 1-methylpentyl, 1,3-dimethylbutyl, n-hexyl, 1-methylhexyl, n-heptyl, isoheptyl, 1,1,3,3-tetramethylbutyl, 1-methylheptyl, 3-methylheptyl, n-octyl, 2-ethylhexyl, 1,1,3-trimethylhexyl, 1,1,3,3-tetramethylpentyl, nonyl, decyl, undecyl, 1-methylundecyl, dodecyl, 1,1,3,3,5,5-hexamethylhexyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, eicosyl or docosyl. One of the preferred meanings of R2 and R4 is, for example, C1-C18alkyl. A particularly preferred meaning of R4 is C1-C4alkyl.
Alkenyl having 3 to 25 carbon atoms is a branched or unbranched radical such as, for example, propenyl, 2-butenyl, 3-butenyl, isobutenyl, n-2,4-pentadienyl, 3-methyl-2-butenyl, n-2-octenyl, n-2-dodecenyl, iso-dodecenyl, oleyl, n-2-octadecenyl or n-4-octadecenyl. Preference is given to alkenyl having 3 to 18, especially 3 to 12, for example 3 to 6, in particular 3 to 4 carbon atoms.
Alkenyloxy having 3 to 25 carbon atoms is a branched or unbranched radical such as, for example, propenyloxy, 2-butenyloxy, 3-butenyloxy, isobutenyloxy, n-2,4-pentadienyloxy, 3-methyl-2-butenyloxy, n-2-octenyloxy, n-2-dodecenyloxy, iso-dodecenyloxy, oleyloxy, n-2-octadecenyloxy or n-4-octadecenyloxy. Preference is given to alkenyloxy having 3 to 18, especially 3 to 12, for example 3 to 6, in particular 3 to 4 carbon atoms.
Alkynyl having 3 to 25 carbon atoms is a branched or unbranched radical such as, for example, propynyl
2-butynyl, 3-butynyl, n-2-octynyl, or n-2-dodecynyl. Preference is given to alkynyl having 3 to 18, especially 3 to 12, for example 3 to 6, in particular 3 to 4 carbon atoms.
Alkynyloxy having 3 to 25 carbon atoms is a branched or unbranched radical such as, for example, propynyloxy
2-butynyloxy, 3-butynyloxy, n-2-octynyloxy, or n-2-dodecynyloxy. Preference is given to alkynyloxy having 3 to 18, especially 3 to 12, for example 3 to 6, in particular 3 to 4 carbon atoms.
C2-C25alkyl interrupted by oxygen, sulfur or
is, for example, CH3—O—CH2—, CH3—S—CH2—, CH3—NH—CH2—, CH3—N(CH3)—CH2—, CH3—O—CH2CH2—O—CH2—, CH3—(O—CH2CH2—)2O—CH2—, CH3—(O—CH2CH2—)3O—CH2— or CH3—(O—CH2CH2—)4O—CH2—.
C7-C9phenylalkyl is, for example, benzyl, α-methylbenzyl, α,α-dimethylbenzyl or 2-phenylethyl. Benzyl and α,α-dimethylbenzyl are preferred.
C7-C9phenylalkyl which is unsubstituted or substituted on the phenyl radical from 1 to 3 times by C1-C4alkyl is, for example, benzyl, α-methylbenzyl, α,α-dimethylbenzyl, 2-phenylethyl, 2-methylbenzyl, 3-methylbenzyl, 4-methylbenzyl, 2,4-dimethylbenzyl, 2,6-dimethylbenzyl or 4-tert-butylbenzyl. Benzyl is preferred.
C7-C25phenylalkyl which is unsubstituted or substituted on the phenyl radical from 1 to 3 times by C1-C4alkyl and is interrupted by oxygen, sulfur or
is a branched or unbranched radical such as, for example, phenoxymethyl, 2-methylphenoxymethyl, 3-methylphenoxymethyl, 4-methylphenoxymethyl, 2,4-dimethylphenoxymethyl, 2,3-dimethylphenoxymethyl, phenylthiomethyl, N-methyl-N-phenylmethyl, N-ethyl-N-phenylmethyl, 4-tert-butylphenoxymethyl, 4-tert-butylphenoxyethoxymethyl, 2,4-di-tert-butylphenoxymethyl, 2,4-di-tert-butylphenoxyethoxymethyl, phenoxyethoxyethoxyethoxymethyl, benzyloxymethyl, benzyloxyethoxymethyl, N-benzyl-N-ethylmethyl or N-benzyl-N-isopropylmethyl.
C7-C9phenylalkoxy is, for example, benzyloxy, α-methylbenzyloxy, α,α-dimethylbenzyloxy or 2-phenylethoxy. Benzyloxy is preferred.
C1-C4alkyl-substituted phenyl, which preferably contains 1 to 3, especially 1 or 2 alkyl groups, is, for example, o-, m- or p-methylphenyl, 2,3-dimethylphenyl, 2,4-dimethylphenyl, 2,5-dimethylphenyl, 2,6-dimethylphenyl, 3,4-dimethylphenyl, 3,5-dimethylphenyl, 2-methyl-6-ethylphenyl, 4-tert-butylphenyl, 2-ethylphenyl or 2,6-diethylphenyl.
C1-C4alkyl-substituted phenoxy, which preferably contains 1 to 3, especially 1 or 2 alkyl groups, is, for example, o-, m- or p-methylphenoxy, 2,3-dimethylphenoxy, 2,4-dimethylphenoxy, 2,5-dimethylphenoxy, 2,6-dimethylphenoxy, 3,4-dimethylphenoxy, 3,5-dimethylphenoxy, 2-methyl-6-ethylphenoxy, 4-tert-butylphenoxy, 2-ethylphenoxy or 2,6-diethylphenoxy.
Unsubstituted or C1-C4alkyl-substituted C5-C8cycloalkyl is, for example, cyclopentyl, methylcyclopentyl, dimethylcyclopentyl, cyclohexyl, methylcyclohexyl, dimethylcyclohexyl, trimethylcyclohexyl, tert-butylcyclohexyl, cycloheptyl or cyclooctyl. Preference is given to cyclohexyl and tert-butylcyclohexyl.
Unsubstituted or C1-C4alkyl-substituted C5-C8cycloalkoxy is, for example, cyclopentoxy, methylcyclopentoxy, dimethylcyclopentoxy, cyclohexoxy, methylcyclohexoxy, dimethylcyclohexoxy, trimethylcyclohexoxy, tert-butylcyclohexoxy, cycloheptoxy or cyclooctoxy. Preference is given to cyclohexoxy and tert-butylcyclohexoxy.
Alkoxy having up to 25 carbon atoms is a branched or unbranched radical such as, for example, methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, isobutoxy, pentoxy, isopentoxy, hexoxy, heptoxy, octoxy, decyloxy, tetradecyloxy, hexadecyloxy or octadecyloxy. Preference is given to alkoxy having 1 to 12, especially 1 to 8, for example 1 to 6 carbon atoms.
C2-C25alkoxy interrupted by oxygen, sulfur or
is, for example, CH3—O—CH2CH2O—, CH3—S—CH2CH2O—, CH3—NH—CH2CH2O—, CH3—N(CH3)—CH2CH2O—, CH3—O—CH2CH2—O—CH2CH2O—, CH3—(O—CH2CH2—)2O—CH2CH2O—, CH3—(O—CH2CH2—)3O—CH2CH2O— or CH3—(O—CH2CH2—)4O—CH2CH2O—.
Alkylthio having up to 25 carbon atoms is a branched or unbranched radical such as, for example, methylthio, ethylthio, propylthio, isopropylthio, n-butylthio, isobutylthio, pentylthio, isopentylthio, hexylthio, heptylthio, octylthio, decylthio, tetradecylthio, hexadecylthio or octadecylthio. Preference is given to alkylthio having 1 to 12, especially 1 to 8, for example 1 to 6 carbon atoms.
Alkylamino having up to 4 carbon atoms is a branched or unbranched radical such as, for example, methylamino, ethylamino, propylamino, isopropylamino, n-butylamino, isobutylamino or tert-butylamino.
Di(C1-C4alkyl)amino also means that the two radicals independently of one another are branched or unbranched, such as, for example, dimethylamino, methylethylamino, diethylamino, methyl-n-propylamino, methylisopropylamino, methyl-n-butylamino, methylisobutylamino, ethylisopropylamino, ethyl-n-butylamino, ethylisobutylamino, ethyl-tert-butylamino, diethylamino, diisopropylamino, isopropyl-n-butylamino, isopropylisobutylamino, di-n-butylamino or diisobutylamino.
Alkanoylamino having up to 25 carbon atoms is a branched or unbranched radical such as, for example, formylamino, acetylamino, propionylamino, butanoylamino, pentanoylamino, hexanoylamino, heptanoylamino, octanoylamino, nonanoylamino, decanoylamino, undecanoylamino, dodecanoylamino, tridecanoylamino, tetradecanoylamino, pentadecanoylamino, hexadecanoylamino, heptadecanoylamino, octadecanoylamino, eicosanoylamino or docosanoylamino. Preference is given to alkanoylamino having 2 to 18, especially 2 to 12, for example 2 to 6 carbon atoms.
C1-C18alkylene is a branched or unbranched radical such as, for example, methylene, ethylene, propylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene, octamethylene, decamethylene, dodecamethylene or octadecamethylene. Preference is given to C1-C12alkylene, especially C1-C8alkylene.
A C1-C4alkyl-substituted C5-C12cycloalkylene ring, which preferably contains 1 to 3, especially 1 or 2 branched or unbranched alkyl group radicals is, for example, cyclopentylene, methylcyclopentylene, dimethylcyclopentylene, cyclohexylene, methylcyclohexylene, dimethylcyclohexylene, trimethylcyclohexylene, tertbutylcyclohexylene, cycloheptylene, cyclooctylene or cyclodecylene. Preference is given to cyclohexylene and tertbutylcyclohexylene.
C2-C18alkylene interrupted by oxygen, sulfur or
is, for example, —CH2—O—CH2—, —CH2—S—CH2—, —CH2—NH—CH2—, —CH2—N(CH3)—CH2—, —CH2—O—CH2CH2—O—CH2—, —CH2—(O—CH2CH2—)2O—CH2—, —CH2—(O—CH2CH2—)3O—CH2—, —CH2—(O—CH2CH2—)4O—CH2— or —CH2CH2—S—CH2CH2—.
C2-C18alkenylene is, for example, vinylene, methylvinylene, octenylethylene or dodecenylethylene. Preference is given to C2-C8alkenylene.
Alkylidene having 2 to 20 carbon atoms is, for example, ethylidene, propylidene, butylidene, pentylidene, 4-methylpentylidene, heptylidene, nonylidene, tridecylidene, nonadecylidene, 1-methylethylidene, 1-ethylpropylidene or 1-ethylpentylidene. Preference is given to C2-C8-alkylidene.
Phenylalkylidene having 7 to 20 carbon atoms is, for example, benzylidene, 2-phenylethylidene or 1-phenyl-2-hexylidene. Preference is given to C7-C9-phenylalkylidene.
C5-C8cycloalkylene is a saturated hydrocarbon group having two free valencies and at least one ring unit and is, for example, cyclopentylene, cyclohexylene, cycloheptylene or cyclooctylene. Preference is given to cyclohexylene.
C7-C8bicycloalkylene is, for example, bicycloheptylene or bicyclooctylene.
Unsubstituted or C1-C4alkyl-substituted phenylene or naphthylene is, for example, 1,2-, 1,3-, 1,4-phenylene, 1,2-, 1,3-, 1,4-, 1,6-, 1,7-, 2,6- or 2,7-naphthylene. 1,4-Phenylene is preferred.
A C1-C4alkyl-substituted C5-C8cycloalkylidene ring, which preferably contains 1 to 3, especially 1 or 2 branched or unbranched alkyl group radicals is, for example, cyclopentylidene, methylcyclopentylidene, dimethylcyclopentylidene, cyclohexylidene, methylcyclohexylidene, dimethylcyclohexylidene, trimethylcyclohexylidene, tert-butylcyclohexylidene, cycloheptylidene or cyclooctylidene. Preference is given to cyclohexylidene and tert-butylcyclohexylidene.
A mono-, di- or trivalent metal cation is preferably an alkali metal, alkaline earth metal or aluminium cation, for example, Na+, K+, Mg++, Ca++ or Al+++.
A particularly preferred composition of present invention contains at least one compound of formula I, wherein, if n=1, R1 is phenyl which is unsubstituted or substituted in para-position by C1-C18alkylthio or di(C1-C4alkyl)amino; mono- to penta-substituted alkyphenyl containing together a total of at most 18 carbon atoms in the 1 to 5 alkyl substituents; naphthyl, biphenyl, terphenyl, phenanthryl, anthryl, fluorenyl, carbazolyl, thienyl, pyrrolyl, phenothizinyl or 5,6,7,8-tetrahydronaphthyl, each of which is unsubstituted or substituted by C1-C4alkyl, C1-C4alkoxy, C1-C4alkylthio, hydroxy or amino.
Preference is given to compounds of the formula I in which, if n is 2,
R12 and R13 are phenylene,
X is oxygen or —NR31—, and
R31 is C1-C4alkyl.
Preference is also given to compounds of the formula I in which, if n is 1, R1 is unsubstituted or C1-C4alkyl-, C1-C4alkoxy-, C1-C4alkylthio-, hydroxyl-, halo-, amino-, C1-C4alkylamino- or di(C1-C4-alkyl)amino-substituted naphthyl, phenanthryl, thienyl, dibenzofuryl, carbazolyl, fluorenyl or a radical of the formula II
R7, R8, R9, R10 and R11 independently of one another are hydrogen, chlorine, bromine, hydroxyl, C1-C18alkyl, C2-C18alkyl interrupted by oxygen or sulfur; C1-C18alkoxy, C2-C18alkoxy interrupted by oxygen or sulfur; C1-C18alkylthio, C3-C12alkenyloxy, C3-C12alkynyloxy, C7-C9phenylalkyl, C7-C9phenylalkoxy, unsubstituted or C1-C4alkyl-substituted phenyl; phenoxy, cyclohexyl, C5-C8cycloalkoxy, C1-C4alkylamino, di(C1-C4-alkyl)amino, C1-C12alkanoyl, C3-C12alkanoyl interrupted by oxygen or sulfur; C1-C12alkanoyloxy, C3-C12alkanoyloxy interrupted by oxygen or sulfur; C1-C12alkanoylamino, C3-C12alkenoyl, C3-C12alkenoyloxy, cyclohexylcarbonyl, cyclohexylcarbonyloxy, benzoyl or C1-C4alkyl-substituted benzoyl; benzoyloxy or C1-C4alkyl-substituted benzoyloxy;
or
or else in formula II the radicals R7 and R8 or the radicals R8 and R11, together with the carbon atoms to which they are attached, form a benzo ring, R15 is hydroxyl, C1-C12alkoxy or
R18 and R19 independently of one another are hydrogen or C1-C4alkyl,
R20 is hydrogen,
R21 is hydrogen, phenyl, C1-C18alkyl, C2-C18alkyl interrupted by oxygen or sulfur; C7-C9phenylalkyl, C7-C18-phenylalkyl which is unsubstituted or substituted on the phenyl radical from 1 to 3 times by C1-C4alkyl and is interrupted by oxygen or sulfur, or else the radicals R20 and R21, together with the carbon atoms to which they are attached, form a cyclohexylene ring which is unsubstituted or substituted from 1 to 3 times by C1-C4alkyl,
R22 is hydrogen or C1-C4alkyl,
R23 is hydrogen, C1-C18alkanoyl, C3-C18alkenoyl, C3-C12alkanoyl interrupted by oxygen or sulfur; C2-C12alkanoyl substituted by a di(C1-C6-alkyl)phosphonate group; C6-C9cycloalkylcarbonyl, benzoyl,
R24 and R25 independently of one another are hydrogen or C1-C12alkyl,
R26 is hydrogen or C1-C4alkyl,
R27 is C1-C12alkylene, C2-C8alkenylene, C2-C8alkylidene, C7-C12phenylalkylidene, C5-C8cycloalkylene or phenylene,
R28 is hydroxyl, C1-C12alkoxy or
R29 is oxygen or —NH—,
R30 is C1-C18alkyl or phenyl, and
s is 1 or 2.
Preference is likewise given to compounds of the formula I in which, if n is 1,
R1 is phenanthryl, thienyl, dibenzofuryl, unsubstituted or C1-C4alkyl-substituted carbazolyl; or is fluorenyl; or R1 is a radical of the formula II
R7, R8, R9, R10 and R11, independently of one another are hydrogen, chlorine, hydroxyl, C1-C18alkyl, C1-C18alkoxy, C1-C18alkylthio, C3-C4alkenyloxy, C3-C4alkinyloxy, C2-C18alkanoyloxy, phenyl, benzoyl, benzoyloxy or
R20 is hydrogen,
R21 is hydrogen, phenyl or C1-C18alkyl, or else the radicals R20 and R21, together with the carbon atoms to which they are attached, form a cyclohexylene ring which is unsubstituted or substituted from 1 to 3 times by C1-C4alkyl,
R22 is hydrogen or C1-C4alkyl, and
R23 is hydrogen, C1-C18alkanoyl or benzoyl.
Particular preference is given to compounds of the formula I in which, if n is 1, R7, R8, R9, R10 and R11 independently of one another are hydrogen, C1-C4alkylthio or phenyl.
Of particular interest is a composition containing at least one compound of the formula I in which
R2, R3, R4 and R5 independently of one another are hydrogen, chlorine, C1-C18alkyl, benzyl, phenyl, C5-C8cycloalkyl, C1-C18alkoxy, C1-C18alkylthio, C1-C18alkanoyloxy, C1-C18alkanoylamino, C3-C18alkenoyloxy or benzoyloxy; or else the radicals R2 and R3 or the radicals R3 and R4 or the radicals R4 and R5, together with the carbon atoms to which they are attached, form a benzo ring, R4 is additionally —(CH2)p—COR15 or —(CH2)qOH, or, if R3, R5 and R6 are hydrogen, R4 is additionally a radical of the formula III,
R15 is hydroxyl, C1-C12alkoxy or
R16 and R17 are methyl groups or, together with the C atom to which they are attached, form a C5-C8cycloalkylidene ring which is unsubstituted or substituted from 1 to 3 times by C1-C4alkyl,
R24 and R25 independently of one another are hydrogen or C1-C12alkyl,
p is 1 or 2, and
q is 2, 3, 4, 5 or 6.
Also of particular interest is a composition containing at least one compound of the formula I in which at least two of the radicals R2, R3, R4 and R5 are hydrogen.
Of special interest is a composition containing at least one compound of the formula I in which R3 and R5 are hydrogen.
Of very special interest is composition containing at least one compound of the formula I in which
R2 is C1-C4alkyl,
R3 is hydrogen,
R4 is C1-C4alkyl or, if R6 is hydrogen, R4 is additionally a radical of the formula III,
R5 is hydrogen, and
R16 and R17, together with the C atom to which they are attached, form a cyclohexylidene ring.
The following compounds are examples of the benzofuran-2-one type which are particularly suitable in the composition of the present invention: 3-[4-(2-acetoxyethoxy)phenyl]-5,7-di-tertbutyl-benzofuran-2-one; 5,7-di-tert-butyl-3-[4-(2-stearoyloxyethoxy)phenyl]benzofuran-2-one; 3,3′-bis[5,7-di-tert-butyl-3-(4-[2-hydroxyethoxy]phenyl)benzofuran-2-one]; 5,7-di-tert-butyl-3-(4-ethoxyphenyl)benzofuran-2-one; 3-(4-acetoxy-3,5-dimethylphenyl)-5,7-di-tert-butylbenzofuran-2-one; 3-(3,5-dimethyl-4-pivaloyloxy-phenyl)-5,7-di-tert-butyl-benzofuran-2-one; 5,7-di-tert-butyl-3-phenylbenzofuran-2-one; 5,7-di-tert-butyl-3-(3,4-dimethylphenyl)-benzofuran-2-one; 5,7-di-tert-butyl-3-(2,3-dimethylphenyl)benzofuran-2-one.
Also of special interest is a composition containing at least one compound of the formula V
in which
R2 is hydrogen or C1-C6alkyl,
R3 is hydrogen,
R4 is hydrogen or C1-C6alkyl,
R5 is hydrogen,
R7, R8, R9, R10 and R11, independently of one another are hydrogen, C1-C4alkyl or C1-C4alkoxy, with the proviso that at least two of the radicals R7, R8, R9, R10 or R11 are hydrogen.
Very particular preference is given to a composition containing at least one compound of the formula Va or Vb
or a mixture of the two compounds of the formula Va and Vb.
Long chain N,N-dialkylhydroxylamine antioxidants useful in the composition of the present invention are those disclosed in U.S. Pat. No. 4,876,300, which is incorporated herein by reference.
The long chain N,N-dialkylhydroxylamine antioxidants useful in the composition of the present invention include those of formula (VI)
wherein T1 and T2 are independently alkyl of 6 to 36 carbon atoms, preferably 12-36 carbon atoms and most preferably 16-18 carbon atoms. Of particular interest is the long chain hydroxylamine for formula (VI) wherein T1 and T2 are the same and are a straight chain alkyl of 18 carbon atoms.
The hydroxylamine antioxidants in the present compositions and methods are, for example, N,N-dioctylhydroxylamine, N,N-dilaurylhydroxylamine, N,N-didodecylhydroxylamine, N ,N-ditetradecylhydroxylamine, N,N-dihexadecylhydroxylamine, N,N-dioctadecylhydroxylamine, N-hexadecyl-N-tetradecylhydroxylamine, N-hexadecyl-N-heptadecylhydroxylamine, N-hexadecyl-N-octadecylhydroxylamine, N-heptadecyl-N-octadecylhydroxylamine, N-methyl-N-octadecylhydroxylamine and N,N-di(hydrogenated tallow)hydroxylamine. Compounds of special interest are those where T1 and T2 are each dodecyl, tetradecyl, hexadecyl or octadecyl; or where T1 is hexadecyl and T2 is tetradecyl, heptadecyl or octadecyl; or where T1 is heptadecyl and T2 is octadecyl.
The long chain hydroxylamine antioxidant in the present invention may be for example the N,N-di(alkyl)hydroxylamine produced by the direct oxidation of N,N-di(hydrogenated tallow)amine (Irgastab® FS-042, Ciba Specialty Chemicals Corp.).
The substituted hydroxylamine antioxidants of the present invention are for example those described in U.S. Pat. Nos. 4,666,962, 4,666,963, 4,678,826, 4,753,972, 4,757,102, 4,760,179, 4,929,657, 5,057,563, 5,021,479, 5,045,583 and 5,185,448 the disclosures of which are hereby incorporated by reference. These include the Michael addition products from the reaction of the hydroxylamines of formula VI with any α,β-unsaturated ketone, ester, amide, or phosphonate; and also includes Mannich-type condensation products from the reaction of the hydroxylamines of formula VI with formaldehyde and secondary amines. Also included are O-alkenyl substituted analogues of the hydroxylamines as disclosed in U.S. Pat. No. 5,045,583. also includes non-hindered substituted hydroxylamines as disclosed in U.S. Pat. No. 5,185,448 and acyl derivatives of the unsubstituted hydroxylamine antioxidants for example such as those disclosed in U.S. Pat. No. 5,021,479.
The substituted hydroxylamines may be for example O-allyl-N,N-dioctadecylhydroxylamine or O-n-propyl-N,N-dioctadecylhydroxylamine or N,N-di(hydrogenated tallow)acetoxyamine.
The nitrones may be for example as described in U.S. Pat. No. 4,898,901, which is hereby incorporated by reference.
The nitrones of are for example of the formula (X)
The nitrones of may be the corresponding oxidation products of the unsubstituted hydroxylamines. That is to say, the nitrones may be nitrone analogues of the unsubstituted hydroxylamines. The nitrones may be for example, N-benzyl-α-phenylnitrone, N-ethyl-1-methylnitrone, N-octyl-α-heptyinitrone, N-lauryl-α-undecylnitrone, N-tetradecyl-α-tridcyinitrone, N-hexadecyl-α-pentadecylnitrone, N-octadecyl-α-heptadecylnitrone, N-hexadecyl-α-heptadecylnitrone, N-ocatadecyl-α-pentadecylnitrone, N-heptadecyl-α-heptadecylnitrone, N-octadecyl-α-hexadecylnitrone, N-methyl-a-heptadecylnitrone and the nitrone derived from N,N-di(hydrogenated tallow)hydroxylamine.
The amine oxides of are for example those disclosed in U.S. Pat. Nos. 5,081,300, 5,162,408, 5,844,029, 5,880,191 and 5,922,794, the relevant parts of each incorporated herein by reference.
The amine oxides are for example saturated tertiary amine oxides as represented by general formula (XI):
Examples of structures of formula (XI) are where G1 and G2 are independently benzyl or substituted benzyl. It is also possible for each of G1, G2, and G3 to be the same residue. G1 and G2 may also independently be alkyl groups of 8 to 26 carbon atoms, for example alkyl groups of 10 to 26 carbon atoms. G3 may be an alkyl group of 1 to 22 carbon atoms, for example methyl or substituted methyl. Also, the present amine oxides include those wherein G1, G2, and G3 are the same alkyl groups of 6 to 36 carbon atoms. The aforementioned residues for G1, G2, and G3 are, for instance, saturated hydrocarbon residues or saturated hydrocarbon residues containing at least one of the aforementioned —O—, —S—, —SO—, —CO2—, —CO—, or —CON— moieties. Those skilled in the art will be able to envision other useful residues for each of G1, G2, and G3 without detracting from the present invention.
The saturated amine oxides may also includes poly(amine oxides). By poly(amine oxides) is meant tertiary amine oxides containing at least two tertiary amine oxides per molecule. Illustrative poly(amine oxides), also called “poly(tertiary amine oxides)”, include the tertiary amine oxide analogues of aliphatic and alicyclic diamines such as, for example, 1,4-diaminobutane; 1,6-diaminohexane; 1,10-diaminodecane; and 1,4-diaminocyclohexane, and aromatic based diamines such as, for example, diamino anthraquinones and diaminoanisoles.
Also included are tertiary amine oxides derived from oligomers and polymers of the aforementioned diamines. Useful amine oxides also include amine oxides attached to polymers, for example, polyolefins, polyacrylates, polyesters, polyamides, polystyrenes, and the like. When the amine oxide is attached to a polymer, the average number of amine oxides per polymer can vary widely as not all polymer chains need to contain an amine oxide. All of the aforementioned amine oxides may optionally contain at least one —O—, —S—, —SO—, —CO2—, —CO—, or —CONG4- moiety. For instance, each tertiary amine oxide of the polymeric tertiary amine oxide may contain a C1 residue.
Specific examples of preferred antioxidants of the present invention are one or more compounds selected from
Irgastab® FS-042 is available from Ciba Specialty Chemicals. Genox™ EP is available from GE Specialty Chemicals. O-allyl-N,N-dioctadecylhydroxylamine is as prepared in Example 3 of U.S. Pat. No. 5,045,583. N-octadecyl-a-heptadecylnitrone is as prepared in Example 3 of U.S. Pat. No. 4,898,901.
The antioxidants of this invention are provided in compositions of this invention in a minor amount based on the weight of the edible organic substance, which amount is effective as an antioxidant, i.e. sufficient to stabilize, or retard the deterioration of, the edible organic substances to be stored and used to prepare foods in a normal and acceptable manner. The amount of antioxidant employed is generally any amount which may have a significant stabilizing effect. The amount of the compounds of this invention present may depend on the desired period of stability of the edible organic substance and the rate of deterioration of the edible organic substance. Thus, increased amounts of the compound of the present invention may be employed when an increased storage life of the edible organic substance before use is desired. Frequently, the compounds of the present invention will be provided in an amount of at least about 0.005%, preferably at least about 0.01%, by weight based on the weight of the edible organic substance up to a maximum of 5%, preferably up to about 1%. Concentrations of about 0.1 or more weight percent of the compounds of the present invention based on the edible organic substance are frequently employed in accordance with the invention. At concentrations in excess of about 5% by weight based on the weight of the edible organic substance, little benefit in increased stability is generally observed.
The presence of the compounds of the present invention usually does not materially affect the manner in which the edible organic substance is formulated or in which it is used to prepare foods. The compounds of the present invention are preferably uniformly admixed in the edible organic substance. The compounds of the present invention may be added at the time of food preparation or may be intimately premixed with the edible fat or fatty oils to stabilize them prior to food preparation.
It is often convenient to provide an edible fat or fatty oil composition in which the volume of the product can easily be handled, particularly when the composition must be transported for its use in food preparation. On the other hand, this invention is applicable to large food processing plants where large volumes of edible organic substance are stored and used in food preparation. The compounds of the present invention, due to their low toxicity and low concentrations which can be effectively employed, are especially suitable for stabilization of large volume doughs such as pastry, cake and biscuit premix such as are used in the baking industry. Also, use in other large scale food production plants such as pet food and other animal feeds are other applications where the compounds of the present invention are especially suitable.
A combination of antioxidants is frequently used in edible fats and fatty oils and foods containing them. The compounds of the present invention may be utilized in conjunction with other food antioxidants to obtain desirable combinations of properties of stability and carry-through. The other food antioxidants can be used in an amount of from about 0.01-0.1% by weight based on the weight of the edible organic substance. They may also be combined with other food additives such as emulsifiers, suspension agents and colorings to provide the desired qualities in the final food product. Examples of such additional food antioxidants include the following:
Corn oil (3 g) stripped of natural tocopherols was oxidized in stoppered 50 ml Erlenmeyer flasks in a shaker oven (Lab-Line Instrument, Inc, Melrose Park, Ill.). Lipid oxidation was followed by measuring perioxide values colorimetrically, and hexanal by static headspace gas chromatography. Periodie values were determined by the ferric thiocyanate method (Chapman, R. A.; Mackay, K. The estimation of perioxides in fats and oils by the ferric thiocyanate method. J. Am. Oil Chem. Soc. 1949, 26, 360-363), modified for safety reasons using choloform:methanol (3:1, v/v) instead of benzene:methanol as solvent. Propanol was determined by static headspace gas chromatography (Frankel, E. N. Formation of headspace volatiles by thermal decomposition of oxidized fish oils vs. oxidized vegetable oils. J. Am. Oil. Chem. Soc. 1993, 70, 767-772). Aliquots of oil samples (0.20 g) were weighed into 22-ml headspace vials, sealed and equilibrated at 80° C. for 10 min in an HS-40 headspace autosampler. An aliquot of the headspace was then injected in an autosystem gas chromatograph (Perkin-Elmer, Norwalk, Conn.) equipped with a capillary DB-1701 column, 30 m long, 0.32 mm id, and 1 μm film thickness (J&W Scientific, Folsom, Calif.). The injector and detector temperatures were 180 and 200° C., respectively. The oven temperature was controlled isothermally at 65° C. Hexanal was quantified by using standard solutions of known concentrations. All analyses were carried out in duplicate.
The activity of the antioxidants was evaluated by determining peroxide values and hexanal using corn oil stripped of natural tocopherols after oxidation at 50 and 60° C. Peroxide values measurements are classical measurements of hydroperoxides that are generally accepted in antioxidant evaluations. This measure is useful at relatively low levels of oxidation and the temperatures used in this study which are sufficiently mild so that hydroperoxides are not markedly decomposed. Hexanal determinations are measurements of hydroperoxide decomposition which may be more closely related to flavor deterioration and rancidity than peroxide values. Antioxidants in accordance with the present invention that were tested were (1) 042—an N,N-di(alkyl)hydroxylamine produced by the direct oxidation of N,N-di(hydrogenated tallow)amine (commercially available from Ciba Specialty Chemicals Corporation Irgastab® FS-042) and Irganox® HP-136—3-(3,4-dimethylphenyl)-5,7-di-tertbutyl-benzofuran-2-one. The antioxidants were tested at 100 and 200 ppm and compared with the commercial antioxidants BHA, BHT and TBHQ and commercial natural antioxidants tocopherol mixtures at the same concentration and a rosemary extract at 250 and 500 ppm.
For the evaluations at 50° C., an endpoint was selected of 8 days for both peroxide values and hexanal contents during the propagation stage where the rate of oxidation is accelerated. The results of the evaluations are shown in Tables 1-2.
For the evaluations at 60° C., an endpoint was selected of 3 days for peroxide values and 4 days for hexanal contents during the propagation stage where the rate of oxidation is accelerated. The results of the evaluations are shown in Tables 3-4.
This application is a divisional of U.S. Ser. No. 10/538,891, filed Jun. 14, 2005, pending, which is a 371 application of PCT/EP/2003/50954, filed Dec. 8, 2003, which claims priority to U.S. Provisional Ser. No. 60/434,715, filed Dec. 18, 2002, all of which are herein incorporated by reference.
Number | Date | Country | |
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60434715 | Dec 2002 | US |
Number | Date | Country | |
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Parent | 10538891 | Jun 2005 | US |
Child | 12221005 | US |