BACKGROUND OP THE INVENTION

Chemicals having the cyclopentanol skeleton are known in the art of perfumery. Examples may be found in Arctander, Perfume and Flavor Chemicals (1969) . For example, iso- butenyl-cyclopentanol which has the structure

is identified as compound No. 376 in Actander. Its fragrance is described therein as powerful, herbaceo s-floral odor of rather poor tenacity.

Arctanier compound No. 942 is dihydrocyclol which has the structure

and is described as having a mild relatively sweet woody- piney odor of moderate tenacity.

Chemicals having the 2,2,3-trimethylcyclopentene skeleton are also known in the art of perfumery and flavor chemistry. For example, 2 2,3-trimethyl-3-cyclopenten-l-acetaldehyde having the structure

has been found in oils of Juniperus communis L. and Lavandin The corresponding acid has been found in Olibanum oil.

U.S. Patent No. 4,052,341 discloses the use in fragrance compositions of 3-methyl-5-(2,2,3-trimethylcyclopent -3- en-l-yl)pentan-2-ol which has the structure

This compound is described as possessing a strong, precious woody odor reminiscent of Sandalwood oil.

SUMMARY OF THE INVENTION

In accordance with the present invention it has been found that compounds having the structure

wherein the dashed line may be either a carbon-carbon single bond or carbon-carbon double bond are useful as fragrance materials. It will be recognized that the chemicals of this invention can exist in different stereoisomeric forms. The foregoing structural formula is intended to embrace the individual stereoisomers, as well as mixtures of the various stereoisomers of the substituted cyclic alcohols of this invention.

The present invention also provides efficient and economical processes for preparing these compounds. Thus, for example, the compound having the structure

can be prepared by reacting cyclopentanone or a de¬ rivative of cyclopentanone, for example the morpholine anamine of cyclopentanone having the structure

with 2 , 2, 3-trimethyl-3-cycloρenten-l-acetaldehyde having the structure

to produce a compound having the structure

which upon hydrogenation yield compound 1_.

Alternatively, compound J5 may be selectively reduced, for example, with sodium borohydride to yield a compound having the structure

It has also been found that an admixture of compounds 1_ and ^~ is also useful as a fragrance material in place of either of the individual compounds.

Finally, in accordance with the present invention it has been found that fragrance compositions can be prepared by incorporating in these compositions Compound 1_ or Compound 2 or a mixture thereof in amounts effective to impart fragrance to the composition.

DETAILED DESCRIPTION OF THE INVENTION

Compounds having the structure

wherein the dashed line may be either a carbon-carbon single bond or a carbon-carbon double bond have been prepared. The compounds exhibit soft, warm woody notes with powdery nuances rendering these compounds useful as fragrance materials. These compounds exhibit similar odor characteristics and may be used individually or as mixtures in fragrance applications. Geometrical and optical isomers

CI ^* :?I

^■

of these compounds may be separated by techniques known to the art. However, such separation is not necessary, since such mixtures of isomers can be employed directly without further separation.

Additionally, mixtures of these compounds wherein the dashed line may be either a carbon-carbon single bond or a carbon-carbon double bond exhibit fragrance properties similar to those of the individual compounds.

The following reaction scheme illustrates the various processes of the present invention for conveniently and inexpensively preparing such compounds:

Specifically, Compound 1 _^ can be prepared by Aldol condensati (see Modern Synthetic Reactions, chapter 10, by H. O. House) of cyclopentanone or a derivative of cyclopentanone, for example its morpholine ena ine, with 2,2,3-trimethyl-3- cyclopenten-1-acetaldehyde 4_ to provide directly, or after acidic work-up, the unsaturated ketone 5_. Compound 5_ is then hydrogenated by conventional techniques such as treatment with hydrogen at an elevated temperature and pressure in the presence of catalyst and a solvent to provide Compound 2..

Compound "* may be prepared in an analagous manner. First, cyclopentanone is reacted with 2,2,3-trimethyl-3-cyclopenten 1-acetaldehyde to provide the Aldol condensation product 5_. Compound 5_ is then selectively reduced by treatment with a metal hydride such as di-isobutylaluminum hydride or with sodium borohydride to provide Compound 2^. Mixtures of compounds 1 _^ and 2 _^ exhibit fragrance properties similar to those of either of the individual compounds. Therefore, such a mixture can be readily substituted for either compoun in fragrance applications. Such a mixture can be prepared by mixing the separately prepared compounds in desired amounts.

Compound 1_, Compound 2 or a mixture thereof are readily incorporated into fragrance compositions for use in detergents, soaps, perfumes, bath preparations, hair preparations, cosmetics preparations, and the like.

When so employed the compound or mixture should desirably be present in an amount from about 0.1% to about 80% by weight based upon the weight of the composition.

OM?I_

A number of examples are provided hereinafter to illustrate the preferred methods of synthesis of the compounds of this invention: Gas Liquid Chromatography (GLC) analyses were obtained with a Hewlett-Packard Model 5840 A or Perkin- Elmer Model 3920 gas chromatograph using either a 10 ft, 2mm ID glass column packed with 2% Carbowax 20M on Chromosorb G 100/120, or a 12 ft, 2 nun Id glass column packed with 3% OV-101 on Chromosorb WHP 100/120. Nuclear Magnetic Resonance (NMR) spectra were recorded with a Varian Associates T-60A or XL 100 spectrometer, using tetramethylsilane as the internal reference. Infrared (IR) spectra were obtained with a Perkin-Elmer 137 Infracord. Mass spectra (MS) , were obtained with a Hewlett-Packard 5985 Mass Spectrometer.

Unless otherwise indicated weights are in grams, temperatures are in degrees centigrade and pressures are in mm Hg.

There are also set forth hereinafter several examples illustrating fragrance compositions which include the compounds of the present invention. All of these examples are intended only to illustrate the preferred embodiments of this invention and are not in any way intended to limit the scope thereof.

2,2,3-Trimethyl-3-cyclopenten-l-acetaldehyde (150 g) , 1-morpholino-l-cyclopentene (154g) and dry benzene (50mL) were heated together at reflux for 24 h. The

OMPI

solution was cooled, aqueous 5% hydrochloric acid (400 mL) added, and the mixture stirred for 1.5 h at 20". The organic layer was separated and washed successively with 5% hydrochloric acid (1-L), 5% sodium bicarbonate (300 mL) and water (4x150 mL) . Solvent was removed, and the residue distilled to provide the desired product b. ₅ 128-131° (143g) PMR (CDCL ₃ ) 0.8 (3H, ), 1. (3H, ), 1.6 (3H, ^* bs) 5.2 (IH, bs) 6.4-6.8 (IH, m) , 1.6-3.0 (9H, complex, IR (neat) 2995, 1 1775500,, 1155440, 12, 10, 810 cm ^"1 . MS (m/e, Example 2

A solution of potassium hydroxide (86g) in water (62 mL) and 2,2,3-trimethyl-3-cyclopenten-l-acetaldehyde (465g) were added simultaneously, over 4 h to a vigorously stirred mixture of cyclopentanone (515g) and water (610 mL) at about 0°. The mixture was stirred at 0° for a further 3 h, and then neutralized with hydrochloric acid. The reaction mixture was extracted with benzene (2x500 mL) , and the combined organic extracts washed to neutrality. Solvent and unreaσted cyclopentanone were removed by distillation. The residue was dissolved in benzene

(1.5 L) , oxalic acid (6g) added, and the mixture heated at reflux for 20 h with removal of water formed using a Dean and Stark trap. The reaction mixture was cooled, washed to neutrality and, distilled to give an oil b _{1 5} 125-127° (310g) . Which was shown by GLC and spectral data to be the desired product.

Example 3

The product of Example 1 (120g) , butyl alcohol (70 mL) , potassium hydroxide (50 mg) and copper bromite (7g) were charged to a 500 mL autoclave and the stirred mixture heated at 155-160° under 300 psi of hydrogen. When gas uptake had ceased, the reactor was cooled (20°) , evacuated, and purged with nitrogen. Solids were removed by filtration, solvent evaporated, and the residue distilled to provide the desired product, b ₅ 107-110° (95g) . PMR (CDCL )60.8 (3H,s), 1.0 (3H, s) , 1.0 (3H,s), 4.1 (IH, bs) , 5.2 (IH, bs) , 1.2-3 (14H, complex), 1.2-2.0 IH, exchanged with D,0) . IR(neat) 3400, 2900, 1000, 910 cm ^"1 . MS(m/e) 107, 108, 93, 121, 222.

A solution of the product of Example 1 (99.6g) in methanol (150 mL) was added dropwise, over 1.2 h to a stirred solution of sodium borohydride (13.Og) in methanol (300 mL) , with cooling, such that the reaction temperature was maintained at 0°-3°. When the addition was complete the reaction temperature was allowed to rise to 10° and agitation was continued for a further 4h. The mixture was acidified with dilute hydrochloric acid (25°) and the product extracted with ether. The organic layer

was washed to neutrality, dried, and distilled to provide an oil b. - 125-127° (77.1g) which was shown by GLC and spectral analysis to be a mixture of Compounds 2_.

Example 5

The following illustrates the utility of Compound L in fragrance compositions of the chypre type. Compound 1_ is the novel compound of this invention as previously defined.

CHYPRE pts/wt Component

260 Oil Bergamot

130 ^' Oil Orange Sweet

200 Methyl Ionone 20 Oil Rose

50 Jasmine Absolute

5 Oil Basil Sweet

5 Oil Estragon

3 Benzyl Salicylate 3 Oil Ylang Extra

6 Cinnamic Alcohol 18 Eugenol

3 Aldehyde C-14

2 10% Sol. Aldehyde C-12 MNA in Diethyl Phthalate Odorless

10 10% Sol. Aldehyde C-ll Undecylenic in Phthalate Odorless

10 Civet Absolute

40 Coumarin

35 Labdanum Resinoid

30 Musk Ketone

35 Oakmoss Absolute

35 Oil Patchouly

5 Vanillin

55 Oil Vetiver Reunion

100 Compound 1

1000

Example 6

The following illustrates the utility of Compound 2 in fragrance compositions of the santal type. Compound _2 is the novel compound of this invention as previously defined.

SANTAL pts/wt Component

90 Terpineol

220 Oil Cedarwood

50 Oil Cassia

80 Coumarin

40 Musk Xylene

80 Oil Vetiver

400 Compound 2

40 Resinold Styrax

1000

Example 7

The following illustrates the utility of a mixture of compounds 1 _^ and 2_ as described in a fragrance composition exhibiting a Sandalwood base fragrance.

SAND&LWOOD BASE pts/wt Component

20 Oil Balsam Gurjon

80 Oil Amyris

100 Osyrol BBA

800 Mixture of Compounds 1 _^ and 2_ (50/50 w/w)

1000

As will be obvious to one skilled in the art, many modi¬ fications, variations, and alterations can be made in the practices of this invention without departing from the spirit and scope thereof as set forth in the claims which follow.