GB1560286A - Spiranic derivatives of dihydrofuran useful as perfuming and flavour-modifying ingredients - Google Patents

Description

(54) SPIRANIC DERIVATIVES OF DIHYDROFURAN USEFUL AS PERFUMING AND FLAVOUR MODIFYING INGREDIENTS (71) We, FIRMENICH SA, a Swiss company of 1, Route des Jeunes, Geneva.

Switzerland, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: 2,6,10,10 - Tetramethyl - 1 - oxa - spiro [4.5]deca - 3,6 - diene, having the formula

was described in the art several years ago.

for example in Swiss Patent no. 544,733.

Whereas the above compound never presented any interest for the main in the art, at least with respect to its organoleptic properties, it was found surprisingly that isomeric derivatives, having the formula

(wherein one of the symbols R represents a methyl group and the other a hydrogen atom) possess interesting arganoleptic properties and they can be advantageously used as odourand flavour-modifying ingredients.

Consequently, the present invention relates to novel compounds of formula I as defined hereinabove, as well as to a perfume and flavour-modifying composition comprising a compound of formula I as an active ingredient.

The present invention further relates to a method for improving, enhancing or modifying the organoleptic properties of perfumed products or of foodstuffs, feedstuffs, bever ages, pharmaceutical preparations or tobacco products which comprises adding thereto a small but effective amount of a compound of formula I, as defined hereinabove.

In the field of perfumery, compounds I are characterized by their original and powerful odour which presents a fresh, green, natural and flowery note reminescent of that of mint leaves, clary sage, or even black currant in certain instances. Moreover, compounds of formula I possess a fruity note reminescent of that of citrus fruits such as grapefruits.

Owing to the particular richness and complexity of its scent, which according to prior knowledge is quite exceptional for this type of derivative, compounds of formula I can be widely used. They may enter in the preparation of various perfume compositions, such as chypre, fruity, woody, flowery, rose, "fougére" and lavender-like compositions.~ Compounds of formula I are, moreover, much appreciated for creating masculine-type compositions wherein they develop a particularly pleasant fresh and natural character.

The olfactive effects which can be achieved by making use of compounds of formula I depend on the concentration used, as well as on the nature of the other ingredients to which they are admixed in a given perfume composition. Interesting effects can be achieved by the use of about 0.05% by weight of the compounds of the invention based on the total weight of the composition. More typical effects are achieved by using between 0.1 and 5% by weight of the composition. Higher amounts, up to 20% or even more, can be used when particular olfactive effects are desired.

Compounds of formula I can also be used advantageously as a sole ingredient or in admixture with at least one other perfuming ingredient and/or suitable diluent or carrier for the preparation of perfumed products, such as soaps, detergents, household materials and cosmetic preparations.

In the field of flavours, compounds of formula I are characterized by their fruity gustative note, at the same time green and woody, reminiscent of the taste of black currant. Compounds of formula I can therefore be advan tageously used for the preparation of various artificial flavours, for example, fruit flavours such as black currant, raspberry or other red berry flavour, or even mint flavour. In the aromatic compositions in which they are incorp orated, compounds of formula I develop.

in most cases, a fresh, herbal and fruity gustative note which improves the natural character of the compositions.

Compounds of formula I may thus be widely used, especially for flavouring foodfeedstuffs, beverages, pharmaceutical preparation or even tobacco products. Gustative effects such as those described above can be achieved by using compounds of formula I in amounts between 0.01 and 10 ppm by weight of the flavoured material.

Preferred amounts are between 0.1 and 2.0, in certain cases 5.0, ppm. Larger amounts may be used when particular gustative effects are desired.

2,6,7,10 - Tetramethyl - 1 - oxa - spiro [4.5]deca - 3,6 - diene and 2,6,9,10 - tetramethyl - 1 - oxa - spiro [4.5] deca - 3,6 diene, which are novel compounds, can be prepared from the corresponding alicyclic ketone of formula

(possessing either a single or a double bond at the 2,3 - position and wherein one of the symbols R represents a methyl group and the other a hydrogen atom) by (a) reacting it with but - 1 - yn - 3 - ol in the presence of a base when a single bond is present at the 2,3-position, or with an organometallic derivative thereof when a double bond is present at the 2,3-position, to afford a compound of formula

(wherein the symbols R are as defined as hereinabove); and (b) reducing the triple bond of the compound of formula III by means of a hydrogenation in the presence of a partially deactivated catalyst and finally treating the thus obtained hydrogenation product with an acidic reagent, when a double bond is present at the 2,3-position, or by treating the compound of formula III with an acidic reagent to afford the compound of formula I in admixture with a compound having the formula

(wherein the symbols R are as defined as hereinabove) and finally separating the constituents of the thus obtained mixture by means of a fractional distillation, when a single bond is present at the 2,3-position.

Accordingly, the present invention also consists in a process for preparing a compound of formula I as described hereinabove.

In accordance with one embodiment of the present process, 2,5,6 - trimethyl - cyclohex 2 - en - 1- one and 2,3,6 - trimethyl - cyclo- hex - 2 - en - 1 - one-i.e. the compounds of formula II wherein a double bond is present at the 2,3-position-will be converted into 2,6,9,10 - tetramethyl - 1 - oxa - spiro [4.5] - deca - 3,6 - diene and 2,6,7,10 - tetramethyl1 - oxa - spiro[4.5]deca - 3,6 - diene, respectively. Such a synthetic method may be illustrated as follows

In the above reaction scheme, X represents a halogen atom, such as Cl, Br or I.

In accordance with a further embodiment of the present process, mixtures in various proportions of 2,6,9,10 - tetramethyl - 1 oxa - spiro [4.5] deca - 3,6 - diene and 2,6,7,10 - tetramethyl - 1 - oxa - spiro [4.5] - deca - 3,6 - diene may be easily prepared from 2,3,6 - trimethyl - cyclohexanone--i.e.

the compound of formula II wherein a single bond is present at the 2,3-position-by reacting this latter compound with but - 1 - yn - 3 - ol according to the method described in Swiss Patent no. 544,733. The relative amounts of the constituents of the resulting mixtures may vary within wide limits, depending on the reaction conditions or on the method of purification.

Each of the reaction steps of the above process may be effected in accordance with usual techniques, and these will be described in a more detailed way in the examples given hereinbelow.

Alicyclic ketones of formula II, used as starting materials, are commercially available products. These compounds can also be prepared from known compounds by known techniques.

To avoid any doubt it is here noted that formula I includes all possible spiranic stereo- isomers. For practical and economical reasons, the compounds of formula I that are used will be in the form of a mixture of stereoisomers.

as directly obtained from the above described process.

The examples given hereinafter illustrate.

but do not limit, the present invention. In the examples, the temperatures are given in degrees centigrade and the abbreviations have, of course, the definition usual in the art.

Example 1 2,6,9,10 - Tetramethyl - 1 - oxa - spiro [4.51deca- 3,6 - diene a) To a cold (00) mixture of 65 g of methyl iodine, 14.4 g of magnesium turnings and 150 ml of anhydrous ether there was added dropwise a solution of 21 g of but - 1 - yn - 3 owl in 50 ml of anhydrous ether. The reaction mixture was further stirred for 2 hours, then allowed to warm to room temperature, and finally reacted with 35 g of 2,5,6 - trimethyl cyclohex - 2 - en - 1 - one in 75 ml of anhydrous ether. After having been heated at reflux for 3 hours and then cooled to room temperature, the reaction mixture was hydrolazed bv means of a saturated aqueous solu tion of NH4CI. After separation of the organic layer, washing, drying and distillation, there were obtained 40 g (800/) of 1 - hydroxy 25.6 - trimethyl - 1 - (but - 1 - yn - 3 hvdroxv - 1 - yl) - cyclohex - 2 - ene, b.p.

1O(#1100/.20 Torr.

IR: 3350, 2200 cm NMR: 0. & 2.2 (6H, 2 s); 1.38 (1H, d, J=6.5 cps); 1.42 (1H, d, J=6.5 cps); 1.78 (3H, m); 4.45 (1H, m); 5.3 (1H, m) 8 ppm b) 31.5 g of the above compound in solution in 350 ml of methanol were hydrogenated at room temperature and under atmospheric pressure, in the presence of 0.5 g of Lindlar catalyst (partially deactivated Pd catalyst). After consumption of 3.1 litres of hydrogen, filtration and evaporation, there were tained 30.8 g (95%) of 1 - hydroxy - 2,5,6 trimethyl - (1 - but - 1 - en - 3 - hydroxy 1 - yl) - cyclohex - 2 - ene. The compound thus prepared was used for the next reaction step without any further purification.

c) To a cold (00) solution of 7 g of the above compound in 50 ml of petroleum ether (b.p. 3050%), there were added dropwise, under nitrogen atmosphere, 5 ml of aqueous 30% H2SO4. The reaction mixture was further stirred for 1 hour, then neutralized by means of NaHCO,, washed and dried. From the organic layer there were obtained upon distillation, 5.7 g (85%) of 2,6,9,10 - tetramethyl - 1 - oxa - spiro[4.Sjdeca - 3,6 diene.

IR: 3070, 3020, 1100--1000, 875, 808, 755.

718 cm-' NMR: 0.8-1.1 (6H); 1.26 (3H, d, J=6.5 cps); 1.29 (3H, d, J=6.5 cps); 1.57 (3H, m); 5.32 (1H, m); 5.54 (2H, m); 5.78 (2H.

8 ppm MS: M4=192; m/e=177, 159, 136, 121, 109, 93, 77, 43.

2,6,7,10 - Tetramethyl - 1 - oxa - spiro[4.5] deca - 3,6 - diene a') The following reactants were treated in the conditions given in paragraph a) above hereinabove: 21.9 g of magnesium turnings 98 g of ethyl bromide in 250 ml of anhy drous tetrahydrofurane (THF) 31.5 g of but - 1 - yn - 3 - owl in 250 ml of anhydrous TIIF 41.4 g of 2,3,6 - trimethyl - cyclohex - 2 en - 1 - one There were thus obtained 39.4 g (80%) of 1 - hydroxy - 2,3,6 - trimethyl - 1 - (but 1 - yn - 3 - hydroxy - 1 - yl) - cyclohex 2 - ene, m.p. 114123 .

IR: 3575, 3400 cm~ NMR: 1.08 (3H, d, J=6.5 cps); 1.42 (3H, d, J=7 cps); 1.62 (3H, s); 1.6--2.2 (8H.

m); 2.70 (1H, broad s); 3.05 (broad s); 4.50 (1H, m) 8 ppm MS: m/e=190, 175, 157, 142, 131, 115, 105.

91, 79, 69, 55, 43.

b') 37.4 g of the above compound in 300 ml of ethyl alcohol were hydrogenated at room temperature and under atmospheric pressure in the presence of 2 g of palladium catalyst (5% on charcoal) and 0.2 g of quinoline. After consumption of the theoretical amount of hydrogen and treatment as described in paragraph b above, there were obtained 37.8 g (100%) of 1 - hydroxy - 2,3,6 trimethyl - 1 - (but - 1 - en - 3 - hydroxy 1-yl)-cyclohex-2-ene.

c') 37.8 g of the above compound were reacted as described in paragraph c above with 10 ml of aqueous 30% H,SO4 to afford 27.8 g (80%) of 2,6,7,10 - tetramethyl - 1 oxa - spiro[4.5]deca - 3,6 - diene, b.p. 53540/0.2 Torr.

IR: 3060, 1665 cm-' NMR: 0.82 (3H, d, J=6 cps); 1.26 (3H, d, J=7 cps); 1.49 (3H, s); 1.63 (3H, s); 1.5-2.2 5H, m); 4.85 (1H, q, J=6 cps); 5.41 (1H, m); 5.72 (1H, d, J=6 cps) 8 ppm MS: M+=192; m/e=177, 159, 150, 135, 123.

107, 91, 79, 67, 55, 43.

2,3,6 - Trimethyl - cyclohex - 2 - en - 1 one used hereinabove as starting material was prepared from 2,5,6 - trimethyl - cyclohex 2 - en - 1 - one after treatment of the latter by means of p - toluenesulfonic acid (3-5 % at 1500, in the presence of an excess of ethylene-glycol. The desired compound.

which is obtained in a 85% yield, was found identical to a sample prenared according to J. Org. Them. 37, 2340 (1972).

Example 2 2,6,7,10 - Tetramethyl - 1 - oxa - spirof4.51 - deca - 3,6 - diene and 2,6,9,10 - Tetramethyl 1 - oxa - spiro[4.51deca - 3,6- diene a) To a mixture of 45 g of sodium hydroxide and 150 ml of anhydrous ether there were added, under stirring and external cooling, 28 g of 2,3,6 - trimethyl - cyclohexanone and 16 g of but - 1 - yl - 3 - ol. After addition of the reactants, the mixture was heated for 16 hours, then cooled to room temperature and finally diluted with water. The separated organic layer finally gave, after distillation, 30.2 g (72% of 1 - hydroxy - 2,3,6 - trimethyl - 1 - (but - 1 - yn - 3 - hydroxy 1 - yl) - cyclohexane, b.p. 105115o/0.02 Torr.

b) 28.4 g of the above compound, mixed with 50 g of H,PO4 60% in water, were heated at 700 for 6 hours, After cooling to room temperature the reaction mixture was extracted with petroleum ether (b.p. 3050o) and the organic layer washed with aqueous 5% NaHCO,, then with water and finally distilled on a Vigreux column. There were thus obtained 16 g of a reaction product (b.p.

45--700/0.02 Torr) containing, according to vapour phase chromatography analysis, ca.

70 /O of the desired mixture and 30% of byproducts.

The reaction mixture as obtained above was finally submitted to a fractional distillation giving first 9.4 g of a 90:10 mixture of 2,6,9,10 - tetramethyl - 1 - oxa - spiro [4.5]- deca - 3,6 - diene and 2,6,7,10 - tetramethyl 1 - oxa - spiro[4.51deca- 3,6 - diene, respectively (b.p. 53--590/0.01 Torr).

The above mentioned proportions are easily determined by mass spectrometry, after comparison of the fragmentation intensities at m/e 136 and 150, respectively.

A further fraction, having b.p. 6570 0.2 Torr, was obtained from the above distillation and identified as a mixture of 2,5,6 trimethyl - 1 - butenoyl - cyclohex - 1 - ene and 2,3,6 - trimethyl - 1 - butenoyl - cyclohex - 1 - ene, respectively.

IR: 1700--1620, 970 cm"' NMR: 0.8-1.2 (6H); 1.48 (3H, s); 1.92 (3H, d of d, Jl=6 cps, J2=3 cps); 5.9-7.0 (2H) 8 ppm MS: Me=192; m/e=177, 149, 135, 107, 91.

81, 69, 55, 41.

Example 3 A base perfume composition was prepared by mixing the following ingredients (parts by weight): Linalool 200 Lavandin oil 200 Isononyl acetate 150 p - t - Butyl - cyclohexyl acetate 100 Di - isobutylcarbinyl acetate 100 "Citrata" mint oil 50 Lemon oil 30 Methyl - ionone 20 Hydroxycitronellal 20 4 - Isopropyl - cyclohexylmethanol** 10 1,1 -Dimethyl-4-acetyl-6-t- butylidane 10 Decylic aldehyde 10%* 10 Total 900 *in diethyl phthalate **available from Firmenich SA, Geneva, Switzerland (see for example, British Paten. No. 1,416,658).

The above base possesses a rather pleasant odour reminiscent of that of lavandin oil and may be conveniently used for the preparation of perfumed products such as shampoos or bubble baths, for example.

By adding to 70 g of the above base 30 g of a 10% solution of 2,6,9,10 - tetramethyl 1 - oxa - spiro[4.5]deca - 3,6 - diene in diethylphthalate, a new perfume composition possessing a fresher, more natural and more flowery odour than that of the above base was obtained.

When in the above example, 2,6,9,10 - tetramethyl - 1 - oxa - spiro[4.5]deca - 3,6 diene is replaced by an identical amount of 2,6,7,10 - tetramethyl - 1 - oxa - spiro[4.5]deca - 3,6 - diene or of the mixture of 2,6,9,10 - tetramethyl - 1 - oxa - spiro [4.5] - deca - 3,6 - diene and 2,6,7,10 - tetramethyl- 1 - oxa - spiro[4.5]deca - 3,6 - diene prepared in Example 2, analogous effects are observed.

Example 4 A base perfume composition for a masculine Eau de Toilette was prepared by mixing the following ingredients (parts by weight): Bergamot oil dist. 160 p - t - Butyl - cyclohexylacetate 100 Galbanum resinoid 50 / g 80 Absolute oak moss descolorized 50 e 80 Pentadecanolide 10%* 80 Cedryl acetate 60 Thibetine 10%* 40 Cedrene 40 Lemon oil 40 Vetiveryl acetate 40 Florida orange oil 40 - Isomethylionone 40 Synthetic civette 10%* 20 Lavender oil 20 Oppoponax oil 10%* 10 Eugenol 10 Coriander oil 10 Nutmeg oil 10 4-I sopropyl - cyclohexylmeth anol** 10 a - lonone 10 Total 900 *in diethyl phthalate **available from Firmenich SA, Geneva, Switzerland, see, for example, British Patent No. 1,416,658).

By adding to 90 g of the above base 5 g of 2,6,9,10 - tetramethyl - 1 - oxa - spiro [4.51deca - 3,6 - diene a new perfume composition with an odour possessing a better defined lifting character was obtained. The said odour, which is, moreover, richer than that of the above base, presents an original flowery note.

When, in the above example, 2,6,9,10 tetramethyl - 1 - oxa - spiro [4.5] deca - 3,6diene is replaced by an identical amount of 2,6,7,10 - tetramethyl - 1 - oxa - spirof4.5]- deca - 3,6 - diene or of the mixture 2,6,9,10 tetramethvl - 1 - oxa - spiro [4.5] deca - 3,6diene and 2,6,7,10 - tetramethyl - 1 - oxa spiro [4.5 ]deca - 3,6 - diene prepared in Example 2, analogous effects are observed.

Example 5 Two syrups of raspberry and black currant type, respectively, were prepared by diluting 1 part by weight of commercial syrup with 4 and 9 parts by weight, respectively, of water. The beverages thus obtained were flavoured with a proportion of 0.3 and 0.5 ppm, respectively, of 2,6,9,10 - tetramethyl 1 - oxa - spiro[4.5]deca - 3,6 - diene.

The flavoured beverages were subjected to organoleptic evaluation by a panel of experienced tasters whose judgment was expressed as follows: -the flavoured raspberry svrup possessed an improved top note and an overall aroma which was fuller and fresher than that of the unflavoured syrup, -the flavoured black current syrup showed a fuller one. It possessed moreover a better defined herbal and fruity note.

When, in the above example, 2,6,9,10 methyl - 1 - oxa - spiro[4.5]deca - 3,6 diene is replaced by an identical amount of 2,6,7,10 - tetramethyl - 1 - oxa - spiro[4.5]deca - 3,6 - diene or of the mixture of 2,6,9,10 - tetramethyl - 1 - oxa - spiro [4.5]- deca - 3,6 - diene and 2,6,7,10 - tetramethyl1 - oxa - spiro[4.5]deca - 3,6 - diene prepared in Example 2, analogous effects are observed.

WHAT WE CLAIM IS:- 1. A compound having the formula

wherein one of the symbols R represents a methyl group and the other a hydrogen atom.

2. 2,6,9,10 - Tetrainethyl - 1 - oxa - spiro [4.5] deca - 3,6 - diene.

3. 2,6,7,10 - Tetramethyl - 1 - oxa - spiro [4.5] deca - 3,6 - diene.

4. A perfume or a flavour-modifying composition which comprises a compound of formula I, as defined in claim 1, as an active ingredient.

5. A perfume composition which comprises a compound of formula I, as defined in claim 1, and at least one other perfuming ingredient and/or an excipient of a diluent.

6. A flavour-modifying composition which comprises a compound of formula I, as defined in claim 1, and at least one other flavourmodifying ingredient and/or an excipient or a diluent.

7. A method for improving, enhancing or modifying the organoleptic properties of perfumes or perfumed products, or of foodstuffs feedstuffs, beverages, pharmaceutical preparations or tobacco products which comprises adding thereto a small but effective amount of a compound of formula I, as defined in

Claims (1)

1. claim 1.

   8. Process for preparing a compound of formula I, as defined in claim 1, which comprises (a) reacting an alicyclic ketone of formula

   (possessing either a single or a double bond at the 2,3-position and wherein one of the symbols R represents a methyl group and the other a hydrogen atom) with but - 1 - yn - 3 ol in the presence of a base when a single bond is present at the 2,3-position, or with an organometallic derivative thereof when a double bond is present at the 2,3-position, to afford a compound of formula

   (wherein the symbols R are defined as hereinabove); and (b) reducing the triple bond of the compound of formula m by means of a hydrogenation in the presence of a partially deactivated catalyst and finally treating the thus obtained hydrogenation product with an acidic reagent, when a double bond is present at the 2,3-position, or treating the compound of formula III with an acidic reagent to afford the compound of formula I in admixture with a compound having the formula

   (wherein the symbols R are defined as hereinabove) and finally separating the constituents of the thus obtained mixture by means of a fractional distillation, when a single bond is present at the 2,3-position.

   9. Process according to claim 8, which comprises using as an organometallic derivative of but - 1 - yn - 3 - ol a compound of formula xMg-=IMgX V wherein the symbol X represents a halogen atom.