CA1128536A - Nor-camphanyl-substituted pyrans, method for their synthesis and use thereof in perfumery - Google Patents

Abstract

Abstract Norcamphanyl-subfitituted pyrans useful as olfactory components of perfume fo mulations, and having the formula:

Description

S~i NOVEL NORCAMPHANYL-SUBSTITUTED PYRANS, METHOD
FOR THEIR SYNTHESIS AN~ USE THEREOF IN_PERFUMERY

Technical Field This invention is concerned with certain novel chemicals containing a bicyclo[2.2.1]heptane moiety and an oxacyclohexane or oxacyclohexene moiety, a method for synthesis of such chemicals, and the use of such chemi-cals as olfactory constituents of perfume formulations.
' '`
Background Art Considerable time and effort are expended by re-saarch chemists in the search for new and inexpensive chemicals which can be used as flavor and fragrance modi-fiers or enhancers in various consumable materials.These substances are used to reduce or replace those natural compounds presently employed which are in diminishing or sporadic supply. They also are employed in creating entirely new flavors and fragrances.
Certain chemicals having the pyran ring have been found to be useful for imparting fragrance and/or flavor to compositions of which they are constituents. For example, ~apanese application Serial No. 7,4011-073 published March 14, 1974, disclose 2,5-diethyltetra-hydropyran chemicals having a rose-like scent, while 3-hydroxy-2-methyl-1,4-pyran, or maltol, is disclosed in "Perfume and Flavor Chemicals", Arctander Vol. IL, No. 1831, as possessing "a warm-fruity, caramellic-swePt odor with emphasis on the caraway note in the dry state."
U.S. Patent No. 3,901,924, granted August 26, lg75, discloses certain l,l-dialkylnaphthopyrans, as weIl as certain chypre and fougere type perfume formulations of ~, :
.

2~3~ 1 , which these pyrans are constituents. Examples of these pyrans are the following:
Rl R2~1~o ~ ~nd wherein each of R} and R2 represents a lower alkyl group.
~ .S. Patent No. 4,010,2B6, gran~ed March 1, 1977, discloses various substituted spiropyrans which exhibi~
a variety of odors and/or flavors, including those characterized as spicy, dill, green, floral, herbal, eucalyptol-like, woody, fruity, berry-like, sweet, minty and weedy, and which are useful as ~lavoring and fragrance imparters or modifiers. Examples of the spiropyrans disclosed in this patent are the following:
.

and wherein the dashed lines represent either a carbon-carbon single bond or a c~nrcarkon double bond; and wherein the presence of three dashed lines in a single structure representation indicates a mixture of double bond isomers. Still other spiropyrans which .

~. . .

~Z8S36 are disclosed are the product of the reaction of dihydro verdyl ketone or verdyl ketone with 3-meth~1-3-buten-1-ol, which is represented by the following formula:

Methods of preparation of other pyran chemicals have also been disclosed in the prior art. For example, U.S. Patent No. 2,422,548, granted June 17, 1947, dis-closes a method for the preparation of certain dihydro~
pyran chemicals which comprises reacting a ketone with an unsaturated alcohol containing an unsaturated tertiary carbon atom linked directly by a single bond to a saturated carbon atom which is directly attached to the carbinol carbon atom, in the presence of an acidic condensation catalyst at a temperature of above about 50C, but not sub,stantially above the temperature of dehydration of the alcohol.
In addition, methods of preparation of both rose oxide and nerol oxide, known odoriferous components of Bulgarian rose oil, are disclosed in Tetrahedron Letters, 51, 4507 (1970) by ~. ~. P. Tyman and B. J. Willis.
These chemicals are ,prepared from the reaction of

3-methyl-2-butenal with ~-methyl-1-buten-4-ol under acidic conditions.
The chemicals described in each of the above patents and articles are different in kind from the chemicals of the instant invention from a structural standpoint, and from the standpoint of their fragrance properties. The chemicals of the instant invention ; possess unexpected, unobvious and advantageous pro-perties from the standpoint of ~uality, character or fragrance when used in fragrance compositions.

, ' 1~2B536 Disclosure of Invention _ _ . _ . . ..
In accordance with this invention, there have been discovered novel norcamphanyl-substituted pyrans which are useful in perfume ~o~mulations for imparting a soft, dry woody odor with greenpepper notes to such composi-tions~
More specifically, the present invention i5 con-cerned with chemicals which may be represented by the structural formula:

R

wherein the dashed lines represent either a carbon-carbon single bond or a carbon-carbon double bond, and R is either hydxogen or methyl. According to currently accepted nomencla~ure, and disregarding stereoisomers, the chemicals within this formula are:
When R is hydrogen--2-(2,2-dimethylbicyclo[2.2.13hept-3-yl)-4-methyloxacyclohex-3-ene, 2-(2,2-dimethylbicyclo[2.2.1]hept-3-yl)-4-methyloxacyclohex-4-ene, and 2-(2,2-dimethylbicyclo[2.2.1]hept-3-yl)-4-methyleneoxacyclohexane When R is methyl:
2-(2,2-dimethylbicyclo[2.2.1]hept-3-yl)-4,6-dimethyloxacyclohex-3-ene, 2-(2,2-dimethylbicyclo[2.2.1]hept-3-yl)-4,6-dimethyloxacyclohex-4-ene, and 2-(2,2-dime~hylbicyclo[2.2.1]hept-3-yl)-4-methylene-6-methyloxacyclohexane ` ~Z~3S36 The dimethylbicycloheptane moiety also may be classified as the "norcamphanyl" moiety, while the oxacyclohexane and oxacyclohexene moieties may be classified generally as "pyran" moieties. Hence, for conven:ience the fore-going chemicals will be referred to collectively as"norcamphanyl-subs~ituted pyrans". The present invention is further concerned with methods for preparing the "norcamphanyl-substituted pyrans", and with their use as olfactory components of perfume compositions.
It will be recognized that the chemicals of this invention can exist in several stereoisomeric forms, including the "dextro" and "laevon, as~ well as the "cls", "trans" isomers. The foregoing structural formula is intended to embrace the individual stereo-isomers, as well as mixtures of the various stereo-isomers of the norcamphanyl-substituted pyrans of this invention.

Brief Description of Drawings ~ig. 1 xepresents the infra-red spectrum of the product of Example 1.
Fig. 2 is the proton magnetic resonance spectrum of the product of Example 1.
Fig. 3 and 4 represent the mass spectral data of the product of Example 1.

Best Mode for Carrying Out the Invention -The novel chemicals of this invention are prepared by reacting camphene epoxide, or spiro (3,3-dimethyl-bicyclo[2.2.1]heptane-2,2'-oxacyclopropane), with either 2-methyl-1-penten-4-ol or 2-methyl-1-buten-4-ol in the presence of an acid catalyst. This reaction may be represented by the general equation:

'ZB~3~

S L~-+ ~+'`~
.

_ 10 wherein R and the dashed lines have the meanings set forth above. The proportions of the two reactants is not critical, and either may be employed in molar excess.
For reasons o~ economy, it is preferred to employ the 15 least expensive reactant, i.e., the alkenol, in excess, for example in A molar ratio o~ alkenol to camphene epoxide of from about 1:1 to about 1.5:1.
Acids which may be emplo~ed as a catalyst for these reactions include inorganic acids such as sulfuric 20 acid and perchloric acid, and organic acids such as the sulfonic acids. Cation exchange resins, for example, those containing the sulfonic acid moiety (-SO3H), may be employed.
The reaction conveniently is carried out in an 25 inert organic solvent, preferably an organic hydrocarbon solvent. Such solvents include aromatic solvents such as benzene and toluene, as well as aliphatic solvents such as hexane or heptane.
Once initiated, the reaction is mildly exothermic, ; 30 and it may be allowed to proceed at autogeneous tempera-tures, which may range from about ambient temperature up to about 60-70C. It is desirable, however, to heat the reaction mixture during the latter stages and to remove the water evolved during the reaction in order 3S to maximize the yield of norcamphanyl-substituted pyransO Temperaturesof up to about 120 can be employed.

~ 2~3S3~

The chemicals of this invention are recovered from the reaction mixture through the use of conven-tional procedures, for example, the acid is neutralized and the organic products fractionated to yield a mixture of norcamphanyl-substituted pyran isomers. The mixture may be employed directly, or the isomers may be separated by techniques known to tne art.
In the course of the foregoing reaction, camphene epoxide is converted ln situ to the corresponding aldehyde, i.e., 2,2-dimethylbicyclo~2.2.1]heptane-3-carboxaldehyde, which then reacts with the alkenol. -Consequently, the novel norcamphanyl-substituted pyrans of this invention also can be prepared by similar pro-cedures to those described above, but substituting the aldehyde for the epoxide.
As used herein, the term "alter" is intended to mean "supply or impart an odorant character or note to an otherwise bland, relatively odorless substance, or augment or enhance the existing odor characteristics of an odorant which may be deficient in some regard, or supplement its existing odor impression to modify its quality, character or taste."
One or more of the norcamphanyl-substituted pyrans of this invention and auxiliary perfume inqredients, for example, alcohols, aldehydes, ketones, nitriles, esters, and essential oils, may be admixed so that the combined odors of the individual components produce a desired fragrance. Such perume compositions are carefully balanced harmonious blends of essential oils, axoma chemicals, resinoids and other extracts of natural odorous materials. Each ingredient imparts its own characteristic effect in the composition. Thus, one or more of the norcamphanyl-substituted pyrans ~f this invention can be employed to impart novel characteris-tics into fragrance compositions.

,~ ~

., Such compositions may contain up to about 80 weightpercent of any one or more of the norcamphanyl-subs~ituted pyrans of this invention. Ordinarily, at least about 0.001 weight percent of the norcamphanyl-substituted pyran is required to impart significant odorcharacteristics. Amounts in the range of from about 1 to about 60 weight percent are preferred. The norcamphanyl-substituted pyrans of this invention may be formulated into concentrates containing from about 1 to about 60 weight percent of the chemical in an appro-priate solvent. Such concentrates are then employed to formulate products such as colognes, soaps, etc. r wherein the con~entration of the chemical of this in-vention can be in the range of from ahout 0.001 to about 7 weight percent, depending upon ~he final pro-duct. For example, the concentration of the chemical of this invention will be of the order of about 0.001 to about 0.1 percent in detergents, and of the order o about 0.01 to about 7 weight percent in perfumes and colognes.
The norcamphanyl-substituted pyrans of this invention are useful as olfactory components of perfume compositions for detergents and soaps; space odorants and deodorants; perfumes; colognes; toile~ water, bath preparations such as bath oils and bath solids; hair preparations such as lacquers, brilliantines, pomades and shampoos; cosmetic preparations such as crea~s, deodorants, hand lotions and sunscreens; powders such as talcs, dusting powders and face powders; and the like.
The following Examples are illustrative of the present invention.
ExAMæLE 1 Concentrated (97%) sulfuric acid (0.3 g) was added to 2-methyl-1-penten-4-ol (374 g) with stirring under nitrogen at 69C, and stirring was continued for 0.4 hour at 68-71C. Camphe~ epoxide (446 g) 5i36 g dissolved in hexane ~450 ml) was added to the mixture during one hour at 53 + 2CO Hea~ing was not required for the first half of this mildly exothermic reaction.
A Dean-and-Stark trap was introduced, and the reaction 5 mixture was heated at 87-89C and vigorously agitated ~or 4 hours, during which time 38.5 ml of water was collected.
The reaction mixture was washed with 2% sodium bicarbonate solution ~100 ml) and water (300 ml).
Volatiles were distilled through a 15~24 cm x 3.49 cm I.~. column packed with large ~aschig rings (steam ~ath, water-ejector vacuum). The pot temperature did not exceed 95 at 140 mm Hg. The crude product (761 g) xemaining in the pot was fractionated through the same column, and after a fore-run, a fraction (321 g), b2 107-112 was collected.
The product is a mixture of chemicals having the structures:

~ ~ ~ ~ and as confirmed by the in~ra-red, pmr and mass spectral data shown in Figs. 1-4. This product has a soft, dry woody odor with greenpepper notes. If desired the isomers can be separated by preparative chromatography techniques known to the art. However, such separation is not necessary, and the mixture of isomers can be employed as is~ Employing similar procedures, except that 2,2-dimethylbicyclo[2.2.1~heptane-3-carboxaldehyde was substituted for camphene epoxide, a mixture of the same chemicals has been obtained.

2l353~

Empl~ying procedures and materials similar ~o those described in xample 1, except that 2-methyl-1-buten-4~ol is subs~ituted for 2-meth~ penten-4-ol~
there can be produced a mixture of chemicals having the structures:

~ O~ and LAVENOL PERFU~ FORMULATION
The norcamphanyl-substituted pyran mixture prepared according to Example 1 is lncorporated in the lavendar type perfume formulation specified below to impart its characteristic od~r.

_ _ _ _ _ , Ingredlent Parts ~y Welght . .
OIL ESTRAGON EXTRA ~.5 OIL PETITGRAIN PARAGUAY 1.8 25 MUSK T SPECIAL 3.0 OIL LIME DISTILLED 3.0 HYPERESSENCE I,IATRIX INCOLORE 3.0 OIL CLOVE EXTRA 3.0 OIL CANANGA 3.5 30 OIL PETITGRAIN CITRONNIER 3.7 OIL ROSEMARY EXTRA 3.8 OIL NEROLI 8.2 OIL MANDARIN EXPRESSED 8.3 OIL PATCHOULY 10.0 35 GEP~NYL ACETATE 10.0 TERPINYL ACETATE 11.0 ~i!353~

MUSK AMBRETTE 11.3 LINALYL ~CETATE SYNTHETIC 20.0 OIL SPIKE LAVENDER EXTRA 20.0 SANDELA GD 2C.0 5 VANILLIN 85.1 TINCTURE AMBERGRIS 4:128 24.0 LINALOOL SYNTHETIC 24.0 OIL SAGE CLARY 30.0 OIL OR~NGE BITTER WEST INDIAN 30.5 10 OIL AMYRIS 35.0 OIL GERANIUM ALGERIAN EXTRA 40.0 ~ , _ . .. . .
HELIOTROPIN EXTRA 50.0 OIL LEMON COLD PRESSED 63.5 15 COUMARIN 103.7 OIL LAVENDER FCC BARREME 38-42~ g7.8 OIL LAVANDIN ABRIAL EXTRA 152.0 THE NORCAMPHANYL-SUBSTITUTED PYRAN
PRODUCT OF EXAMPLE 1 225.3 TOTAL , 1150 0 .. _ .

AMBRE PERFUME FORMULATION
The norcamphanyl-substituted pyran product of Example 1 is incorporated in the following Labdanum type perfume formulation to impart its characteristic odor.

.. , . _ . .. . ................ .. . _ Ingredlent Parts bY Weiaht ,, _, .~
CASTOREUM ABSOLUTE
VANILLIN 2 --;
30 RESINOID OLIBANUM EXTRA 2 ~-~
10~ SOL. OIL BALSAM PERV ~-IN D.E.P. 2 50~ SOL. RESINOID BENZOIN SIAM EXTRA
IN D.EoP. 4 35;3~;

THE NORCAMPHANYL-SUBSTITUTED PYRAN

AMB~EINE PERFUME FORMULATION
The norcamphanyl-substituted pyran product of Example 1 is incorporated in the perfume composition specified below.

" , _ . . . . . _ . _ . , --_ 10 Ingre~lent __Parts by We l~ht ~ _ _ . . __ - METHYL NAPHTHYL KETONE 0.2 NOVOVIOL ALPHA 0.2 ALDEHYDE C-14 0,2 10% SOL. BENZALDEHYDE
IN D.E.P. 0.4 3% SOL. MUSQUIN
IN ALCOHOL 1.0 10% SOL. ABSOLUTE~IMMORTELLE
IN D.E.P. ~ 1.0 50% SOL. CASTOREUM ABSOLUTE
IN D.E.P. 1.0 PHENYL ETHYL ALCOHOL l.0 10~ SOL. OIL OLIBANUM EXTRA
IN D.E.P. 1.0 OIL ORANGE SWEET WEST INDIAN 1.0 METHYL IONONE GAMMA PURE 1.5 OIL PATCHOULY LIGHT COLOR 2.0 50% SOL. OLIBANUM EXTRA RESINOID
IN D.E.P. 2.0 10~ SOL. OIL GALBANUM
IN D.E.P. 2.0 50% SOL~ CYSTE ABSOLUTE
IN D.E.P. 3.0 35 ETHYL VANILLIN 3.0 MUSK XYLOL 3.0 STYRAX RESINOID 4.0 ~Z~3S3~

OIL CEDARWOOD WHITE TEXAS 6.0 OIL LEMON COLD PRESSED 8.0 50~ SOL. BENZOIN SIAM RESINOID EXTRA
IN D.E.P. li.0 COUMARIN 15.5 OIL BERGAMOT SYNTHETIC 24.0 THE NORCAMPHANYL-SUBSTITUTED PYRAN
PRODUCT OF EXAMPLE 1 25.0 _ _ , .... .. _ TOTAL _ 125.0 _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ . , . _ _ .

This invention has been described in terms of pecific embodiments set forth in detail, but it should be understood that these are by way of illustra-tion only and that the invention is not necessarily limited thereto. Other modifications and variations will be apparent from this disclosure and may be re-sorted to without departing from the spirit of this invention, as those skilled in the art will readily understand. Accordingly, such variations and modifi-cations are considered to be within the scope of thisinvention and the following claims.

Claims (9)

Claims

1. A norcamphanyl-substituted pyran of the formula:

wherein the dashed lines represent either a carbon-carbon single bond or a carbon-carbon double bond such that two of the three dashed lines represent carbon-carbon single bonds; and wherein R is either hydrogen or a methyl group.

2. A chemical according to claim 1 in which R is hydrogen.

3. A chemical according to claim 1 in which R is a methyl group.

4. A process of synthesizing a chemical according to claim 1 which comprises reacting a member selected from the group consisting of camphene epoxide or 2,2-dimethyl[2.2.1]heptane-3-carboxaldehyde with an alkenol selected from the group consisting of 2-methyl-l-penten-4-ol or 2-methyl-1-buten-4-ol in the presence of an acid catalyst.

5. A process according to claim 4 wherein camphene epoxide is reacted with said alkenol.

6. A process according to claim 5 wherein camphene epoxide is reacted with 2-methyl-1-penten-4-ol.

7. A process according to claim 5 wherein camphene epoxide is reacted with 2-methyl-1-buten-4-ol.

8. A fragrance of perfume compositi.on comprising an amount, in the range of from about 0.001% to about 80 weight percent, of a chemical according to claims 1, 2 or 3, sufficient to impart a soft, dry, woody odor with greenpepper notes to said composition.

9. A fragrance or perfume composition comprising an amount, in the range of from about 1% to about 60% by weight of the composition, of a chemical according to claims 1, 2 or 3, sufficient to impart a soft, dry, woody odor with greenpepper notes to said composition.