Perfuming Ingredient

The present invention relates to perfumery. It concerns more particularly a method for enhancing, improving or modifying the odor properties of a perfuming composition of perfumed product, which method comprises adding to said composition or product a fragrance effective amount of 2-(2,3,4,5,6,7-hexahydro-1,1,4,4-tetramethyl-2(1H)-indenyl)-ethyl acetate.

The invention also provides a perfuming composition containing as a perfuming ingredient 2-(2,3,4,5,6,7-hexahydro-1,1,4,4-tetramethyl-2(1H)-indenyl)-ethyl acetate.

A further object of the invention is to provide a perfumed product containing as a perfuming ingredient 2-(2,3,4,5,6,7-hexahydro-1,1,4,4-tetramethyl-2(1H)-indenyl)-ethyl acetate.

The chemical structure of 2-(2,3,4,5,6,7-hexahydro-1,1,4,4-tetramethyl-2(1H)-indenyl)-ethyl acetate has been known for some time. The compound has in fact been described by R. T. Reddy and Y. R. Nayak in Tetrahedron 42, 4533 (1986). However, these authors only concerned themselves with examining the behavior of isolongifolene in the presence of a hydrogen halogenide, and separated the above-mentioned compound as an intermediate product without recognizing its intrinsic odor properties.

It has now been discovered that 2-(2,3,4,5,6,7-hexahydro-1,1,4,4-tetramethyl-2(1H)-indenyl)-ethyl acetate possess very useful odor properties and that, as a result, it can be used advantageously as a perfuming ingredient for the preparation of perfume bases, perfuming compositions and perfumed products.

The odor properties of this compound are such that it can be used to develop notes of the woody, slightly amber type. This compound is also capable of imparting to the compositions to which it is added a very elegant musky note. These are very fine notes, perfectly convenient for the preparation of alcoholic perfumes or the reconstitution of natural oils, but which can equally be adapted for perfuming products such as shampoos, cosmetic preparations, body deodorants, soaps, powder or liquid detergents, fabric softeners or yet air deodorizers.

The bicyclic ester which is the object of the invention can be used alone in the above-mentioned products or, as is generally the case, in admixture with other perfuming ingredients, with solvents, diluting agents or carriers.

The proportions in which the compound of the invention can be used to achieve the desired perfuming effect vary within a wide range of values. The man skilled in the art is well aware that such concentrations can vary as a function of the specific fragrance effect desired and depends on the coingredients present in a given composition and on the nature of the products to be perfumed.

Thus, in many cases, concentrations of the order of 5-30% by weight, relative to the weight of the composition to which it is added, can be used. These values can of course be lower, for instance of the order of 0.1-0.5, or even 1%, when it is desired to perfume articles such as soaps, detergents or cosmetic preparations.

As coingredients, one can use any of the ingredients currently used in perfumery in admixture with the bicyclic ester of the invention, the usual criteria of physico-chemical stability and odor compatibility being respected.

As previously mentioned, the chemical structure of 2-(2,3,4,5,6,7-hexahydro-1,1,4,4-tetramethyl-2(1H)-indenyl)-ethyl acetate is disclosed in the scientific literature. This compound can be obtained from isolongifolene by treatment with hydrobromic or hydroiodic acid, followed by esterification. The process for its preparation may be schematically represented as follows [see Tetrahedron 42, 4533 (1986)]:

The invention will be illustrated in greater detail in the following non-restrictive examples.

A base composition consisting of a commercial powder detergent, with a neutral odor, was perfumed with 2-(2,3,4,5,6,7-hexahydro-1,1,4,4-tetramethyl-2(1H)-indenyl)-ethyl acetate, using 0.1 and 0.2% by weight of this compound relative to the weight of the base. As a result, a novel base was obtained possessing an odor character of the woody, balsamic and gently amber-musky type.

The thus obtained perfumed base composition was used for the general washing of linen, by means of an automatic washing machine at 60.degree. C. After one cycle of washing and drying, the linen had a persistant and fresh character, and a fine, elegant woody, amber and musky odor.

A perfuming base composition of the "fougere" type was prepared by mixing the following ingredients (parts by weight):

The addition of 30 g of 2-(2,3,4,5,6,7-hexahydro-1,1,4,4-tetramethyl-2(1H)-indenyl)-ethyl acetate to 190 g of the base composition thus prepared resulted in a novel composition whose overall odor character was richer, with a musky and ambrette side. The woody note of the base composition was also strengthened, resulting in increased volume.

A perfuming base composition for a masculine line was prepared as follows (parts by weight):

The addition of 10 g of 2-(2,3,4,5,6,7-hexahydro-1,1,4,4-tetramethyl-2(1H)-indenyl)-ethyl acetate to 90 g of this woody, aromatic, herbaceous base composition resulted in a novel composition whose odor character was much more elegant and round than that of the said base composition. In particular, the citrus note harmonized better. Furthermore, the new composition had a musk-ambrette odor.