Technical field

The present invention relates to the field of perfumery. More particularly, it concerns the use as perfuming ingredients of cyclic oxy compounds. The present invention concerns the use of said compounds in the perfumery industry as well as the compositions or articles containing said compounds.

Prior art

To the best of our knowledge, none of the invention's compounds, nor any close analogue, is known as perfuming compound or as having an odor in general.

Some of the invention's compounds are known perse but are always cited as chemical intermediates, e.g. (Z)-2-(2-pentenyl)-2-cyclopenten-l-ol and its enantiomers (see C. Fehr et al, in Angew. Chem. Int. Ed, 2000, 39, 569), or also 2-pentyl-2- cyclopenten-l-ol (see S. Tamogami et al, in J Pesticide Science, 2004, 29, 200 - CA 143:248221).

However, these prior art documents do not report or suggest any organoleptic properties of the compounds of formula (I), or any use of said compounds in the field of perfumery.

Description of the invention

We have now surprisingly discovered that a compound of formula

in the form of any one of its stereoisomers or a mixture thereof, and wherein R represents a hydrogen atom or a methyl group;

R ² represents a C ₁ -C ₃ linear or branched alkyl group;

R ⁵ represents a hydrogen atom or a C ₁ -C ₃ linear or branched alkyl group; the two R ³ , taken together, represent a carbon-carbon double bond or a CH ₂ group; and the two R ⁴ , taken together, represent a carbon-carbon double bond or a CH ₂ group, or when taken separately represent each a hydrogen atom;

can be used as perfuming ingredient, for instance to impart odor notes of the green, green- watery type.

According to a particular embodiment of the invention, in said formula (I), R ¹ represents a hydrogen atom.

According to a particular embodiment of the invention, said compound (I) is a derivative of formula

wherein R 2 and R 5 have the same meaning as for formula (I) and the dotted line represents a carbon-carbon single or double bond.

According to a particular embodiment of the invention, in said formula (I) or (II), R ² represents a methyl or ethyl group.

According to a particular embodiment of the invention, in said formula (I) or (II), R ⁵ represents a hydrogen atom or a methyl or ethyl group.

According to any one of the above embodiments of the invention, said compounds (I) or (II) are C ₁₀ or C ₁₂ compounds.

For the sake of clarity, by the expression "wherein one dotted line represents a carbon-carbon single or double bond" or "the two R ³ , taken together, represent a carbon- carbon double bond", or the similar, it is meant the normal meaning understood by a person skilled in the art, i.e. that the whole bonding (e.g. solid and dotted line) between the carbon atoms connected by said dotted line is a carbon-carbon single or double bond.

As specific examples of the invention's compounds, one may cite, as non-limiting example, (Z)-2-(2-pentenyl)-2-cyclopenten-l-ol, which possesses a soft green odor, with a watery and sap aspect. The green note is not at all acidic or aggressive as the one of many known perfuming ingredients used to impart green notes. Moreover, it is also noticeable that said compound acts as booster for the overall perfume, exalting the volume, like methyl dihydrojasmonate can do (although with a different olfactive direction).

As other specific, but non-limiting, examples of the invention's compounds, one may cite the following ones in Table 1 :

Table 1 : Invention's compounds and their odor properties

As mentioned above, the odor of the invention's compounds is characterized by a green note, and in many cases (for example for the ethers or the doubly unsaturated alcohols) by a green- watery note. The odor of the invention's compounds is quite different from the one of the know perfuming ingredient 2-pentyl-cyclopentanol, because at least lacking, or not possessing significant, lactonic-coconut notes which are characteristic of the prior art compounds. Said differences lend the invention's compounds and the prior art compounds to be each suitable for different uses, i.e. to impart different organoleptic impressions.

According to a particular embodiment of the invention, the compounds of formula (I) are (Z)-2-(2-pentenyl)-2-cyclopenten-l-ol, (+)-(R,Z)-2-(2-pentenyl)-2- cyclopenten-l -ol or 5 -ethoxy- 1 -pentyl- 1 -cyclopentene.

In particular 5 -ethoxy- 1 -pentyl- 1 -cyclopentene is a new compound, and therefore also an object of the present invention. As mentioned above, the invention concerns the use of a compound of formula (I) as perfuming ingredient. In other words, it concerns a method to confer, enhance, improve or modify the odor properties of a perfuming composition or of a perfumed article, which method comprises adding to said composition or article an effective amount of at least a compound of formula (I). By "use of a compound of formula (I)" it has to be understood here also the use of any composition containing a compound (I) and which can be advantageously employed in perfumery industry.

Said compositions, which in fact can be advantageously employed as perfuming ingredients, are also an object of the present invention.

Therefore, another object of the present invention is a perfuming composition comprising:

i) as perfuming ingredient, at least one invention's compound as defined above;

ii) at least one ingredient selected from the group consisting of a perfumery carrier and a perfumery base; and

iii) optionally at least one perfumery adjuvant.

By "perfumery carrier" we mean here a material which is practically neutral from a perfumery point of view, i.e. that does not significantly alter the organoleptic properties of perfuming ingredients. Said carrier may be a liquid or a solid.

As liquid carrier one may cite, as non-limiting examples, an emulsifying system, i.e. a solvent and a surfactant system, or a solvent commonly used in perfumery. A detailed description of the nature and type of solvents commonly used in perfumery cannot be exhaustive. However, one can cite as non-limiting example solvents such as dipropyleneglycol, diethyl phthalate, isopropyl myristate, benzyl benzoate, 2-(2- ethoxyethoxy)-l-ethanol or ethyl citrate, which are the most commonly used. For the compositions which comprise both a perfumery carrier and a perfumery base, other suitable perfumery carriers, than those previously specified, can be also ethanol, water/ethanol mixtures, limonene or other terpenes, isoparaffins such as those known under the trademark Isopar (origin: Exxon Chemical) or glycol ethers and glycol ether esters such as those known under the trademark Dowanol (origin: Dow Chemical Company).

As solid carrier one may cite, as non-limiting examples, absorbing gums or polymers, or yet encapsulating materials. Examples of such materials may comprise wall- forming and plasticizing materials, such as mono, di- or trisaccharides, natural or modified starches, hydrocolloids, cellulose derivatives, polyvinyl acetates, polyvinylalcohols, proteins or pectins, or yet the materials cited in reference texts such as H. Scherz, Hydrokolloids : Stabilisatoren, Dickungs- und Gehermittel in Lebensmittel, Band 2 der Schriftenreihe Lebensmittelchemie, Lebensmittelqualitat, Behr's VerlagGmbH & Co., Hamburg, 1996. The encapsulation is a well known process to a person skilled in the art, and may be performed, for instance, using techniques such as spray-drying, agglomeration or yet extrusion ; or consists of a coating encapsulation, including coacervation and complex coacervation techniques.

By "perfumery base" we mean here a composition comprising at least one perfuming co-ingredient.

Said perfuming co-ingredient is not of formula (I). Moreover, by "perfuming co- ingredient" it is meant here a compound, which is used in a perfuming preparation or a composition to impart a hedonic effect. In other words such a co-ingredient, to be considered as being a perfuming one, must be recognized by a person skilled in the art as being able to impart or modify in a positive or pleasant way the odor of a composition, and not just as having an odor.

The nature and type of the perfuming co-ingredients present in the base do not warrant a more detailed description here, which in any case would not be exhaustive, the skilled person being able to select them on the basis of his general knowledge and according to intended use or application and the desired organoleptic effect. In general terms, these perfuming co-ingredients belong to chemical classes as varied as alcohols, lactones, aldehydes, ketones, esters, ethers, acetates, nitriles, terpenoids, nitrogenous or sulphurous heterocyclic compounds and essential oils, and said perfuming co-ingredients can be of natural or synthetic origin. Many of these co-ingredients are in any case listed in reference texts such as the book by S. Arctander, Perfume and Flavor Chemicals, 1969, Montclair, New Jersey, USA, or its more recent versions, or in other works of a similar nature, as well as in the abundant patent literature in the field of perfumery. It is also understood that said co-ingredients may also be compounds known to release in a controlled manner various types of perfuming compounds.

By "perfumery adjuvant" we mean here an ingredient capable of imparting additional added benefit such as a color, a particular light resistance, chemical stability, etc. A detailed description of the nature and type of adjuvant commonly used in perfuming bases cannot be exhaustive, but it has to be mentioned that said ingredients are well known to a person skilled in the art.

An invention's composition consisting of at least one compound of formula (I) and at least one perfumery carrier represents a particular embodiment of the invention as well as a perfuming composition comprising at least one compound of formula (I), at least one perfumery carrier, at least one perfumery base, and optionally at least one perfumery adjuvant.

It is useful to mention here that the possibility to have, in the compositions mentioned above, more than one compound of formula (I) is important as it enables the perfumer to prepare accords, perfumes, possessing the odor tonality of various compounds of the invention, creating thus new tools for his work.

For the sake of clarity, it is also understood that any mixture resulting directly from a chemical synthesis, e.g. a reaction medium without an adequate purification, in which the compound of the invention would be involved as a starting, intermediate or end-product could not be considered as a perfuming composition according to the invention as far as said mixture does not provide the inventive compound in a suitable form for perfumery. Thus, unpurified reaction mixtures are generally excluded from the present invention unless otherwise specified.

Furthermore, the invention's compound can also be advantageously used in all the fields of modern perfumery, i.e. fine or functional perfumery, to positively impart or modify the odor of a consumer product into which said compound (I) is added. Consequently, a perfumed article comprising:

i) as perfuming ingredient, at least one compound of formula (I), as defined above; and ii) a consumer product base ;

is also an object of the present invention.

For the sake of clarity, it has to be mentioned that, by "consumer product base" we mean here a consumer product which is compatible with perfuming ingredients. In other words, a perfumed article according to the invention comprises the functional formulation, as well as optionally additional benefit agents, corresponding to a perfume compatible consumer product, e.g. a detergent or an air freshener, and an olfactive effective amount of at least one invention's compound.

The nature and type of the constituents of the consumer product do not warrant a more detailed description here, which in any case would not be exhaustive, the skilled person being able to select them on the basis of his general knowledge and according to the nature and the desired effect of said product.

Non-limiting examples of suitable consumer products can be a perfume, such as a fine perfume, a cologne or an after-shave lotion; a fabric care product, such as a liquid or solid detergent, a fabric softener, a fabric refresher, an ironing water, a paper, or a bleach; a body-care product, such as a hair care product (e.g. a shampoo, a coloring preparation or a hair spray), a cosmetic preparation (e.g. a vanishing cream or a deodorant or antiper spirant), or a skin-care product (e.g. a perfumed soap, shower or bath mousse, oils or gel, or a hygiene product); an air care product, such as an air freshener or a "ready to use" powdered air freshener; or a home care product, such as a wipe, a dish detergent or hard-surface detergent.

Some of the above-mentioned consumer product bases may represent an aggressive medium for the invention's compound, so that it may be necessary to protect the latter from premature decomposition, for example by encapsulation or by chemically bounding it to another chemical which is suitable to release the invention's ingredient upon a suitable external stimulus, such as an enzyme, light, heat or a change of pH.

The proportions in which the compounds according to the invention can be incorporated into the various aforementioned articles or compositions vary within a wide range of values. These values are dependent on the nature of the article to be perfumed and on the desired organoleptic effect as well as the nature of the co -ingredients in a given base when the compounds according to the invention are mixed with perfuming co- ingredients, solvents or additives commonly used in the art.

For example, in the case of perfuming compositions, typical concentrations are in the order of 0.001 % to 10 % by weight, or even more, of the compounds of the invention based on the weight of the composition into which they are incorporated. Concentrations lower than these, such as in the order of 0.01% to 5% by weight, can be used when these compounds are incorporated into perfumed articles, percentage being relative to the weight of the article.

The invention's compounds can be prepared according to a method involving the reduction of the corresponding ketone (see below the Examples) or a method involving a Lindlar reduction of the corresponding alkyne of formula

wherein R 1 , R2 , R 3 and R 5 have the same meaning as for formula (I);

said method optionally further comprising the necessary steps to transform the obtained alkene into the desired compound (I) according to any standard method known to the person skilled in the art. The compounds of formula (II) are also new compounds and therefore are another object of the present invention as useful intermediates.

Examples

The invention will now be described in further detail by way of the following examples, wherein the abbreviations have the usual meaning in the art, the temperatures are indicated in degrees centigrade (°C) ; the NMR spectral data were recorded in CDCI ₃

(if not stated otherwise) with a 360 or 400 MHz machine for 1 H and 13 C, the chemical shifts δ are indicated in ppm with respect to TMS as standard, the coupling constants J are expressed in Hz.

Example 1

Synthesis of compounds of formula (I)

2-(2Z-Pentenyl)-2-cyclopentenol

A solution of 2-(2Z-pentenyl)-2-cyclopentenone (42.0 g, 280 mmol) in Et ₂ 0 (50 ml) was added dropwise in 2 hours to a mechanically stirred suspension of L1AIH4 (5.32 g, 140 mmol) in Et ₂ 0 (100 ml), thus maintaining a gentle reflux. After complete introduction, the mixture was heated for 15 minutes at reflux (water bath), then cooled (icewater bath), hydrolyzed with 5% aqueous NaOH (40 ml) and filtered. The concentrated filtrate (40.5 g) was distilled with a bulb-to-bulb apparatus (70°C oven temp./ (0.1 Torr).

Yield: 39.5 g (93%). Alternative procedure for 2-(2Z-pentenyl)-2-cyclopentenol :

2-Pentynyl-2-cyclopentenol

2-Pentynyl-2-cyclopentenone (29.9 g, 89% pure, 179 mmol) was added at 0°C dropwise in 2 hours to a mechanically stirred suspension of L1AIH4 (2.50 g, 65.8 mmol) in Et ₂ 0 (300 ml). After complete introduction, the mixture was stirred for 30 minutes at 5°C, then hydrolyzed with water (2.5 ml), 5% aqueous NaOH (2.5 ml) and more water (7.5 ml). After 10 min, the suspension was dried (Na ₂ S0 ₄ ), filtered on Celite and the filtrate evaporated and distilled (72°C/ 0.5 Torr). Yield: 23.4 g [76% pure (contains starting ketone)]. Pure 2-pentynyl-2-cyclopentenol was obtained by chromatography (S1O ₂ ; cyclohexane/AcOEt = 8:2).

'H-NMR: 1.14 (t, J=7, 3H), 1.75 (m, 1H), 1.86 (s, OH), 2.15-2.50 (5H), 3.04 (AB, 2H),

4.72 (broad, 1H), 5.28 (broad s, 1H).

1 ³ C-NMR: 12.4 (t), 14.2 (q), 18.5 (t), 29.6 (t), 34.0 (t), 76.3 (s), 78.4 (d), 83.5 (s), 129.3

(d), 141.6 (s).

The two enantiomers of 2-pentynyl-2-cyclopentenol were obtained by enzymatic resolution by applying exactly the conditions described in Angewandte Chemie Int. Ed. 2000, 39, 569.

2-(2Z-Pentenyl)-2-cyclopentenol

Hydrogenation of 2-pentynyl-2-cyclopentenol, using Lindlar-catalyst (10% by weight) in cyclohexane in an atmosphere of ¾ at room temperature afforded the desired product.

(+)-(R,Z)-2-(2-pentenyl)-2-cyclopenten-l-ol

The two enantiomers of 2-(2Z-pentenyl)-2-cyclopentenol are known and were obtained by enzymatic resolution: Angewandte Chemie Int. Ed. 2000, 39, 569.

e.g. (+)-(R,Z)-2-(2-pentenyl)-2-cyclopenten-l-ol

¹³ C-NMR: 14.26, 20.47, 26.19, 29.68, 34.02, 78.94, 125.90, 127.67, 133.02, 144.99. 'H-NMR: 0.97 (t, J=7.5, 3H), 1.72 (m, 2H), 2.08 (m, 2H), 2.19 (m, 1H), 2.28 (m, 1H),

2.39 (m, 1H), 2.89 (m, 2H), 4.64 (b.s., 1H), 5.46 (m, 2H), 5.55 (b.s., 1H).

oc _D : +1.759 (0.18M in CHC1 ₃ )

5-Ethoxy-l-pentyl-l-cyclopentene

Under argon, 55% sodium hydride (3.58 g; 0.082 mol) and anhydrous THF (30 g) were charged in a multi-necked 250 ml round bottom flask and heated to 55°C. 2-pentylcyclopent-2-en-l-ol (8.5 g; 0.0546 mol) was added over 1 hour. The mixture was stirred for another hour at 55°C. Ethyl bromide (12.03 g; 0.1093 mol) was added over 1 hour at the same temperature. After 16 hours the reaction mixture was cooled to 2°C and water (20 g) was slowly added. The aqueous phase was removed. The organic phase was washed with 12.5% aqueous phosphoric acid, 25% aqueous bicarbonate and brine. Drying over anhydrous sodium sulphate, filtration and removal of the solvent, flash chromatography (silica; eluent = heptanes/ ethyl acetate) afforded the target compound. ¹³ C-NMR: 14.1 (q), 15.7 (q), 22.6 (t), 27.3 (t), 28.4 (t), 30.0 (t), 30.1 (t), 31.9 (t), 63.7 (t),

85.7 (d), 127.2 (d), 144.9 (s).

'H-NMR: 0.89 (t, J=6.9, 3H); 1.20 (t, J=7.0, 3H); 1.24-1.36 (m, 4H); 1.39-1.55 (m, 2H);

1.74-1.82 (m, 1H); 2.00-2.24 (m, 4H); 2.35-2.46 (m, 1H); 3.37-3.45 (m, 1H);

3.50-3.58 (m, 1H); 4.33-4.38 (m, 1H); 5.52-5.55 (m, 1H).

Example 2

Preparation of a perfuming composition

An Eau de toilette was prepared by admixing the following ingredients:

Insredient Parts bv weisht

Benzyl acetate 50

Nopyl acetate 40

Vetyveryl acetate 50

Cinnamic alcohol 15

Hexylcinnamic aldehyde 100

10%* Gamma undecalactone 20

Bergamot essential oil 1950

Citral 200

Lemon essential oil 160

10%* Citronellal 30

Coumarin 50

Estragon essential oil 15

Geranium essential oil 20

Clove essential oil 140 3-(l,3-Benzodioxol-5-yl)-2-methylpropanal 40

Hydroxycitronellal 10

10%* Indol 50

Lavender essential oil 400

Alpha iso methyl ionone 200

Moss Base ^υ 40

Patchouli essential oil 110

Petitgrain essential oil 50

Vetyver essential oil 60

3800

* in dipropyleneglycol

1) compounded base having a moss character; origin: Firmenich SA, Geneva,

Switzerland

The addition of 200 parts by weight of (Z)-2-(2-pentenyl)-2-cyclopenten-l-ol to the above-described composition imparted to the latter a remarkable green character with a slight watery twist, and also boosted, exalted and multiplied the strength of the overall odor.

When, instead of the invention's compound, methyl dihydrojasmonate was added, the exalting and multiplying effect was similar but the olfactive effect was in the jasmine, citrusy direction rather than in the green direction as for the invention's compound, providing thus a quite different perfume. Example 3

Preparation of a perfuming composition

A perfuming composition for a shampoo, of the peach/apricot type, was prepared by admixing the following ingredients:

Ingredient Parts by weight

Amyl acetate 20

Ethyl acetoacetate 100 Benzoic aldehyde 20

Hexylcinnamic aldehyde 250

Gamma undecalactone 150

Gamma nonalactone 30

Benzyl benzoate 400

Allyl caproate 50

Citral 50

Dimethyl benzyl carbinyl butyrate 100

10%* Damascenone 50

Gamma decalactone 170

Dihydromyrcenol 150

Phenoxyethyl-iso-butyrate 200

Linalool 300

1%* 2-Isopropyl-4-methylthiazole 50

10%* Cis-Jasmone 50

10%* Ethyl-2-methylbutyrate 150

Linalyl oxide 60

Phenethylol 300

2-Phenoxy-l-ethanol 700

10%* 9-Ethylidene-3-oxatricyclo[6.2.1.0(2,7)]undecane ¹⁾ 50

10%* Ethyl salicylate 50

Benzyl salicylate 150

10%* Vanilline 40

Verdox ^{® 2)} 50

Alpha ionone 30

Wardia ^{® 3)} 80

3800

* in dipropyleneglycol

1) origin: Firmenich SA, Geneva, Switzerland

2) 2-tert-butyl-l-cyclohexyl acetate; origin: International Flavors & Fragrances, USA

3) compounded specialty base having a rose character; origin: Firmenich SA, Geneva, Switzerland The addition of 200 parts by weight of (Z)-2-(2-pentenyl)-2-cyclopenten-l-ol to the above-described peach/apricot shampoo's composition provided to the latter a natural and soft freshness, as well as an incredible volume boosting all the fruity notes present in the original composition.

The addition of other known green notes (such as the derivatives of cis-3-hexenol) did not boost the fruity notes and imparted to the fragrance a green totally different, i.e. acidic, aggressive, note.