Use of campholenenitriles as fragrance

Abstract

It has been found that .alpha.-campholenenitrile with formula A and .gamma.-campholenenitrile with formula B ##STR1## are excellent for use as fragrances, especially as components of fragrance mixtures for perfuming cosmetics or other consumer goods. The two nitriles can be used individually or in mixture with each other.

Description

Compounds with a campholene structure occur naturally as components of essential oils, e.g., .alpha.-campholene aldehyde 2 in juniperberry oil (A. F. Thomas, Helv. Chim. Acta, Vol. 55, 1972, p. 815). .alpha.-Campholene aldehyde has a fresh resinous odor.

Some derivatives of campholene aldehyde 2 with a lengthened side chain have odors suggesting a woody, animal type corrresponding to certain aspects of East Indian sandalwood oil (survey in E.-J. Brunke and E. Klein "Chemistry of Sandalwood Fragrance," in "Fragrance Chemistry" (editor E. Theimer), Academic Press, New York, 1982, p. 424-426)). ##STR2##

In general, there is a constant demand for synthetic fragrances that can be produced to advantage with a uniform quality, remain stable in prolonged storage even in contact with other substances and have desired olfactory properties, i.e., pleasant fragrances that are as natural as possible, are of adqeuate intensity and are capable of having a positive influence on the fragrance of cosmetics or other consumer commodities. It has been found that .alpha.-campholenenitrile of general formula A and .gamma.-campholenetrile of general formula B satisfy this requirement in an excellent manner, because they can be produced with no problem, are extremely stable compounds with a highly individual fragrance characteristic and strong radiant emission and are fragrances that have a variety of uses. Due to their fragrance properties, they can be used as components of perfume oils of a wide variety of odor directions to enrich creative perfumery. Due to their high chemical stability, especially their resistance to acids, they can also be used to advantage to perfume relatively aggressive basic compositions (detergents, household cleaners, etc.). ##STR3##

This invention therefore concerns the use of .alpha.-campholenenitrile with general formula A (also designated below as 4) as well as .gamma.-campholenenitrile with general formula B (also designated below as 6) as perfumes or as components of perfume mixtures for perfuming cosmetic or other consumer commodities. General formulas A and B also include the stereoisomeric forms of campholenenitriles such as those indicated by the zigzag line. Both nitriles A and B can be used in pure form as as a mixture according to this invention.

Nitrile A which corresponds to campholene aldehyde 2 had already been synthesized in 1883 by V. Meyer by action of methyl chloride on camphor oxime. However, at that time the structure of the product was not yet known (V. Meyer, Ber. Dt. Chem. Ges., Vol. 16, 1883, p. 2981). F. Tiemann succeeded in elucidating the structure and assigning formula A to it (F. Tiemann, Ber. Dt. Chem. Ges., Vol. 29, 1896, p. 3006). In the same article this author describes the synthesis of A by the action of dilute sulfuric acid on camphor oxime. Pyrolysis or photolysis of camphor oxime also yields nitrile A (T. Sato and H. Obase, Tetrahedron Letters, 1967, 1633-1636). In addition, A has also been obtained from camphor oxime by the action of phosphorus pentoxide (M. Nazir et al., Pakistan Journal of Science and Industrial Research, Vol. 10, No. 1, 1967, p. 13-16) or concentrated hydrochloric acid (N. G. Kozlov and T. Pekh, Zh. Org. Khim., 1982, 18(5), 1118-1119). A was likewise identified in the reaction mixture of photolysis or pyrolysis of camphor nitrimine (L. J. Winters, J. F. Fisher and E. R. Ryan, Tetrahedron Letters, 1971, p. 129-132).

The literature does not contain any information on the olfactory properties of .alpha.-campholenylnitrile A, and .gamma.-campholenenitrile B is not yet described in the literature at all.

In an appraisal of the fragrance, pure .alpha.-campholenenitrile A has a strongly radiant, fruity and sweet, spicy aroma in the direction of tonka extract and citrus peel with aspects of orris root extract, whereas pure .gamma.-campholenenitrile B has a strong radiant fragrance with a spicy and fresh woody effect and a secondary aspect in the direction of cumin. Both campholenenitriles enhance the head notes and radiation of perfume oils.

The fragrance effects of campholenetriles A and B are original and novel with respect to the pure components and also with respect to mixture thereof. Furthermore, these fragrance effects are surprising in that they clearly differ from the olfactory properties of known campholene derivatives on the one hand and on the other hand they could not have been foreseen from the fragrance properties of other known nitriles. The relatively strong metallic, fatty secondary notes which are undesirable but typical of known aliphatic nitriles such ad decylnitrile, tridecene-2-nitrile, citronellylnitrile or geranylnitrile with citrus main notes do not occur with nitriles A and B. Furthermore, the general experience that the olfactory properties of known fragrances do not permit any compelling inferences regarding the properties of structurally related compounds is also confirmed here because neither the mechanism of fragrance perception nor the influence of chemical structure on fragrance perception have been adequately researched and thus it is not normally possible to preduct whether a modified structure of known perfumes will lead to a change in olfactory properties at all and whether these changes are to be evaluated positively or negatively.

To produce nitriles A and B, the procedure followed may be different. Two alternative reaction pathways have proven especially expedient, namely:

1. Oximation of campholene aldehyde 2 and subsequent dehydration according to the following scheme I: ##STR4##

Starting from .alpha.-campholene aldehyde 2, the rearrangement product of .alpha.-pinene epoxide, the corresponding oxime 3 was synthesized by conventional methods and dehydrated with acetic anhydride to form pure .alpha.-campholenenitrile 4 (A).

2. Rearrangement of camphor oxime 5 according to the following scheme II. ##STR5##

Oxime 5 produced from camphor according to conventional methods was reacted with dilute sulfuric acid according to the procedure described by Tiemann. First a mixture of .alpha.-campholenenitrile 4 and .alpha.-campholenenitrile 6 was formed. By reacting with sulfuric acid for several hours, a practically complete conversion of .alpha.-campholenenitrile to .gamma.-campholenenitrile was achieved. Thus pure .gamma.-campholenenitrile 6 (B) was obtained for the first time.

Independently of the reaction pathway proposed, both nitriles A and B can be produced either as optically active or inactive products starting from optically active or inactive educts, and the pure stereoisomers as well as their mixtures and racemates can also be used according to this invention.

The following examples are presented to illustrate this invention without limiting it.

EXAMPLE 1

______________________________________Perfume oil with a sweetish herbal note a b______________________________________Orange oil 180 g 180 gIsobornyl acetate 300 g 300 gCyclogalbanate 5 g 5 gOil of bergamot 100 g 100 gOil of rosemary, Tunisian 30 g 30 gOil of mugwort 1 g 10 gBase Bigaradia 18* 15 g 15 gApple base* 10 g 10 gDimethyltetrahydrobenzaldehyde 5 g 5 gStyrolyl acetate 20 g 20 gHexyl cinnamaldehyde, alpha 100 g 100 gOil of geranium, Bourbon, synthetic 10 g 10 gPhenethyl alcohol 30 g 30 gCitronellol 100 g 100 gYlanate (p-tert-butylcyclohexyl acetate) 30 g 30 gLignofix* (acetylcedrene) 30 g 30 gOil of patchouli 20 g 20 gStemone (Givaudan) 5 g 5 gGalbanum resinoid 10 g 10 gMusk, Ambrette 20 g 20 gCyclopentadecanolide 20 g 20 g.alpha.-Campholenenitrile -- g 30 gDipropylene glycol 30 g -- g 1080 g 1080 g______________________________________ *Special product of DRAGOCO

Perfume oil a has a sweetish herbal note.

Composition b, which contains about 3% .alpha.-campholenenitrile instead of dipropylene glycol which has a neutral odor, has a powerful fresh fragrance and an interesting hint of fruity tone. It is very suitable for bubble baths.

EXAMPLE 2

______________________________________Perfume oil with a spicy woody character a b______________________________________Evernyl .RTM. 5 g 5 gBrahmanol .RTM. (DRAGOCO) 5 g 5 gEugenol methyl ether 5 g 5 gDecatone .RTM. (Givaudan) 10% in DPG 5 g 5 gGalaxolide .RTM. (IFF) 20 g 20 gNutmeg oil 20 g 20 gLilial .RTM. 30 g 30 gSauge Claree resinoid 35 g 35 gOak moss extract, green, Yugoslavian(50% in DPG) 50 g 50 gIsobutyl quinoline (10% in DPG) 50 g 50 gMusk ketone 60 g 60 gEugenol 80 g 80 gLinalyl acetate 100 g 100 gLavandin oil 100 g 100 gOil of bergamot (free of furocoumarin) 100 g 100 gLignofix (DRAGOCO) 290 g 290 gDipropylene glycol 45 g --.gamma.-Campholene nitrile -- 45 g 1000 g 1000 g______________________________________

Composition a has a powerful spicy, woody aroma whereas when .gamma.-campholenenitrile is added, composition b has a highly desirable hint of sweetish herbal notes (in the direction of lavender) as well as a definite roundness.

EXAMPLE 3

______________________________________Perfume oil with an herbal note a b______________________________________Oil of bergamot 100 g 100 gOil of cedar leaf 150 g 150 gOil of wormwood 30 g 30 gOil of rosemary, Tunisian 45 g 45 gOil of spike, Spanish 20 g 20 gOil of clary 10 g 10 gPeppermint oil, Brazilian 5 g 5 gPhenethyl alcohol 100 g 100 gCitronellol 30 g 30 gDiphenyl ether 10 g 10 gOil of geranium, Bourbon 5 g 5 gLinalool 50 g 50 gLinalyl acetate 60 g 60 gMethylionone, gamma 50 g 50 gYlanate (4-tert-butylcyclohexyl acetate) 50 g 50 gTerpineol, pure 100 g 100 gAnisaldehyde 50 g 50 gLignofix* (acetylcedrene) 100 g 100 gBenzyl salicylate 50 g 50 gAmyl salicylate 70 g 70 gYlang-ylang oil, synthetic 30 g 30 gGalbanum extract 5 g 5 gCoumarin 50 g 50 gCyclopentadecanolide 30 g 30 gDipropylene glycol 40 g --.gamma.-Campholenenitrile -- 40 g 1240 g 1240 g______________________________________ *Special product of DRAGOCO

Perfume oil a has an herbal fragrance complex.

Composition b, which contains about 3% .gamma.-campholenenitrile, has a stronger effect, emphasizes the herbal note and is characterized by a novel tea aspect.

EXAMPLE 4

______________________________________Perfume oil of a floral type a b______________________________________Brahmanol .RTM. 20 g 20 gCitronellol 50 g 50 gPhenethyl alcohol 175 g 175 gIndole 4 g 4 gIsoeugenol 6 g 6 gBenzyl acetate 30 g 30 gLinalool 40 g 40 gTerpineol, pure 240 g 240 gMuguet alcohol*(2,2-dimethyl-3-phenylpropanol) 200 g 200 gCinnamic alcohol 40 g 40 gCitronellyl acetate 20 g 20 gFrambinon* 15 g 15 gBuccoxime* (1,5-dimethyl-8-hydroximinobicyclo[3.2.1]octane) 70 g 70 gDipropylene glycol 90 g 87 g.alpha.-Campholenenitrile (A) -- 2 g.gamma.-Campholenenitrile (B) -- 1 g 1000 g 1000 g______________________________________ *Special product of DRAGOCO

Composition a has a powerful, gently floral note in the direction of lily of the valley with an exotic fruity undertone. Adding small amounts of compounds A and B (composition b) yields a completely different fragrance characteristic in the interesting direction of "white flowers" with "Chypre" aspects.

EXAMPLE 5

The following table illustrates the extremely high stability of .alpha.-campholenenitrile in various basic compositions (in which .gamma.-campholenenitrile can be used similarly). Of the three ratings shown here for stability, mainly "very good" occurs and there is only one "good." Not a single rating of "not good" was obtained.

__________________________________________________________________________ Fragrance stability 1 month at 3 months at Fragrance effect (covering room 1 month room 3 months the perfume base, radiantTest base Dosage temperature at 40.degree. C. temperature at 40.degree. C. effect)__________________________________________________________________________Acidic cleaner (H.sub.3 PO.sub.4) 0,5 SG SG SG G strongAlkaline cleaner 0,5 SG SG SG SG strongSoap, white 1,0 SG SG SG SG strongAll-purpose detergent 0,2 SG SG SG SG very strongwith TAEDAll-purpose detergent, liquid 0,3 SG SG SG SG strongLaundry softener 0,2 SG SG SG SG very strongBubble bath 3,0 SG SG SG SG very strongShampoo 0,5 SG SG SG SG very strongAerosol antiperspirant 4,0 SG SG SG SG strongSpray deodorant 1,0 SG SG SG SG strongVanishing cream, oil/ 0,3 SG SG SG SG very strongwater emulsion__________________________________________________________________________ Stability: SG = very good (no change in note) G = good (minor change in note, acceptable) NG = not good (change in note, not acceptable)

Claims

1. A method of enhancing fragrance of substances, said method comprising adding a small but fragrance enhancing effective amount of a campholenenitrile selected from the group of campholenenitriles of the formula (A) and of the formula (B) below: ##STR6## wherein for formula (A) R.sup.1 equals hydrogen, R.sup.2, R.sup.3 and R.sup.4 equal methyl, and for formula (B) R.sup.1, R.sup.2 and R.sup.3 equal methyl and R.sup.4 equals hydrogen.

2. The method of claim 1 wherein said campholenenitrile is .alpha.-campholenenitrile.

3. The method of claim 1 wherein said campholenenitrile is .gamma.-campholenenitrile.

4. The method of claim 1 wherein said campholenenitrile is a mixture of .alpha.-campholenenitrile and .gamma.-campholenenitrile which has a content of from 0.5% to 99.5% of .alpha.-campholenenitrile and from 99.5% to 0.5% .gamma.-campholenenitrile.

5. A cosmetic fragrance composition which comprises a fragrance carrier and a small but fragrance enhancing effective amount of a campholenenitrile selected from the group consisting of .alpha.-campholenenitrile and .gamma.-campholenenitrile or mixtures thereof.