EP0908173B1 - Use in perfumery of 1-methoxy-2-methyl-3-phenylpropane,1-(2-methoxypropyl)-4-methylbenzene and 3-methoxy-2,2,3,-trimethyl-1-phenylbutane - Google Patents

Description

The present invention relates to the field of perfumery. It relates to, more particularly, the use of 1-methoxy-2-methyl-3-phenylpropane, 1- (2-methoxypropyl) -4-methylbenzene and 3-methoxy-2,2,3-trimethyl-1-phenylbutane in as a fragrance ingredient.

We know from the prior art a number of structural compounds analogues which lend themselves to use as perfuming ingredients. It suits to mention in this context phenylethyl-isopropyl-ether, described in the application EP-0 049 120, as well as phenylethyl-methyl-ether. These two compounds are are very similar in their olfactory notes, which can be described as strongly green with a flowery connotation, which is accompanied by a strong side fairly moldy earthy mushroom.

Mention should also be made of the phenylethyl isoamyl ether described. in US patent 5,248,434 and patent application EP-0 596 493. This ether develops olfactory properties which are very close to those of the two ethers mentioned above, but the green note is even stronger and more aggressive. We find also an earthy-green side evoking the green-earthy note of hyacinth.

All these compounds have also been shown to be stable in the media. chlorinated. This stability is a rare quality and highly sought after in ingredients perfumers intended for use in environments typically aggressive for the perfume, such as for example detergents and chlorinated media. So the problem of finding fragrance ingredients that are stable in such environments remains a permanent news.

Now we have discovered new ethers which have good stability in chlorinated media and which have distinct olfactory notes from those of known compounds, in particular with a more floral connotation and with a character more discreet green.

The preferred compound of the present invention is 1-methoxy-2-methyl-3-phenylpropane. Its smell has a dewy rose leaf note which is very natural. In addition, there is a very nice side of exotic fruit type which evokes the smell of lychee. The smell of this ether is free from the earthy-humic note, mushroom which is found in the known compounds cited above and which is a sub-note little appreciated in the type of applications in functional perfumery to which these compounds are destined. In comparison to the ethers cited which are known as that stable ingredients in bleach, 1-methoxy-2-methyl-3-phenylpropane is by far the most flowery, the most rosy, evoking the smell of citronellol and geraniol. In at the same time, its green side is significantly softer and does not have the green note aggressive common to the known phenylethyl ethers cited, this note being viewed as being a disadvantage of this type of compound suitable for use in oxidizing medium. Finally, the fruity-exotic side of this new molecule brings a very original effect for the application in detergents, in particular in high pH detergents such as bleach.

1-methoxy-2-methyl-3-phenylpropane is a compound known from the prior art. It has been described in Ind. J. Chem. 27B , 314 (1988) without, however, a synthesis for this molecule being reported. Furthermore, this reference nowhere mentions the use of this molecule as a perfuming ingredient.

The invention also relates to two other new compounds which are also suitable for use in bleach. One of these compounds is 1- (2-methoxypropyl) -4-methylbenzene which also has a green note which is accompanied by a strong flowery side. We no longer find the fruity note exotic, but the compound smells of anise and ethyl cinnamate which are also new notes very appreciated in this kind of application.

The other compound is 3-methoxy-2,2,3-trimethyl-1-phenylbutane, of which the smell can be described as floral and fruity. The floral note is of the type floral-animal with phenolic connotations, while the floral note is of the type citrus, typical of grapefruit, intense and very appreciated.

The above-mentioned compounds of the invention show excellent stability in bleach, as will be described later in the examples, and cover the typical aggressive, asphyxiating odor of bleach well.

As is clear from the above, the two compounds according to the present are particularly suitable for use in bleach and, more generally, for use in aggressive media and / or at pH Student. By way of example, mention may be made of detergents containing agents and laundry activators such as tetraacetylethylenediamine (TAED), agents peroxygen bleaching and, in the case of bleach, hypochlorite, but also media containing reducing agents such as products for perms. They are also suitable for other uses in functional perfumery, and cite, as such, applications in liquid or solid detergents intended for treatment of textiles, fabric softeners, or detergent compositions or cleaning products intended for cleaning dishes or various surfaces.

Of course, the use of the compounds according to the invention is not limited to the products mentioned above, they also lend themselves to all other uses common in perfumery, namely the perfuming of soaps and shower or bath gels, products hygiene or hair treatment, shampoo as well as ambient air fresheners or cosmetic preparations, and even for use in fine perfumery, namely in perfumes and eau de toilette.

In the applications mentioned, the compounds according to the invention can be used alone or in admixture with other fragrance ingredients, solvents or adjuvants commonly used in perfumery. The nature and variety of these co-ingredients does not call for a more detailed description here, which cannot be exhaustive, the person skilled in the art being able to choose them from his general knowledge and depending on the nature of the product to be perfumed and the desired olfactory effect. These fragrance ingredients belong to chemical classes as varied as alcohols, aldehydes, ketones, esters, ethers, acetates, nitriles, terpene hydrocarbons, heterocyclic nitrogen or sulfur compounds, as well as original essential oils natural or synthetic. Many of these ingredients are also listed in reference texts such as the book by S. Arctander, Perfume and Flavor Chemicals, 1969, Montclair, New Jersey, USA, or more recent versions, or in other works of a similar nature.

The proportions in which the compounds according to the invention can be incorporated in the aforementioned miscellaneous products vary in a range of values extended. These values are dependent on the nature of the article or product that we want perfume and the desired olfactory effect, as well as the nature of the co-ingredients in a given composition when the compound of the invention is used in mixture with perfume co-ingredients, solvents or adjuvants commonly used in the art.

By way of example, we can cite typical concentrations of the order of 0.1 at 10%, possibly even reaching 20% or more, by weight of these compounds, relative to the weight of perfume composition in which they are incorporated. Concentrations much lower than these can be used when these compounds are directly applied in the perfume of various consumer products mentioned before.

The compounds according to the present invention can be synthesized as described below.

To obtain 1-methoxy-2-methyl-3-phenylpropane (see line (1) of the diagram below), methylcinnamic aldehyde is used which, in the first stage of the synthesis, is hydrogenated in 1- hydroxy-2-methyl-3-phenylpropane using an appropriate catalyst, which may be Raney nickel. The product obtained is then etherified using a common etherification agent, such as for example the MH / CH ₃ X system in which X is a halogen and M is an alkali metal, to obtain the desired product.

The synthesis we use in the production of 1- (2-methoxypropyl) -4-methylbenzene (see line (2) of the diagram below) uses as a product of departure of the 3-bromotoluene which is reacted, after transformation into the compound of corresponding Grignard type, with propylene oxide. 1- (2-hydroxypropyl) -4- methylbenzene thus obtained is then etherified into the final product with an agent etherification, as specified before.

Finally, 3-methoxy-2,2,3-trimethyl-1-phenylbutane (see line (3) of the diagram below) is prepared from 3,3-dimethyl-4-phenyl-2-butanone that it is reacted with the magnesium of a methyl halide, for example bromide or iodide, in order to obtain the 2,3,3-trimethyl-4-phenyl-2-butanol alcohol. Said alcohol is then etherified to the desired final product as described above for the other compounds of the invention.

The invention will now be described in more detail using the following examples, in which abbreviations have the usual meaning in art and NMR data (chemical shift δ) are indicated in ppm compared to TMS as internal standard.

Example 1 Synthesis of 1-methoxy-2-methyl-3-phenylpropane a) 1-hydroxy-2-methyl-3-phenylpropane

19 g (0.133 mol) of methylcinnamic aldehyde were placed in solution in 200 ml of methanol and hydrogenated at room temperature and atmospheric pressure in the presence of 3 g of Raney nickel. After 4 hours and absorption of about 7 L (0.28 mole) of hydrogen, the reaction was stopped. After filtration and concentration of the solution obtained, it was distilled, using a ball oven, at 150 ° C (1x10 ² Pa).

19.3 g of a colorless oil were obtained, representing a theoretical yield of 99%.
Odor: balsamic, warm, cinnamic.
NMR ⁽¹ H): 0.91 (d, J = 7.6Hz, 3H); 1.93 (m, 1H); 2.4 (m, 1H); 2.75 (m, 1H); 3.48 (m, 2H); 7.23 (m, 5H)
SM: 150 (23, M ⁺ ), 132 (27), 117 (55), 91 (100), 65 (16), 39 (20)

b) 1-methoxy-2-methyl-3-phenylpropane

220 ml (1.9 mole) of KH (35% in oil) were placed, under an N ₂ atmosphere, in a 4.5 l reactor and rinsed 4 times with pentane in order to remove all traces of oil. 1.5 l of dry tetrahydrofuran were added before introducing dropwise a solution of 259 g (1.73 mole) of 1-hydroxy-2-methyl-3-phenylpropane and 500 ml of dry tetrahydrofuran. It was left to stir for 15 hours at room temperature. Then 285 g (2.01 mole) of methyl iodide were introduced dropwise over 2 hours and allowed to stir for another 2 hours at room temperature. A possible excess of KH was hydrolyzed by introducing 50 ml of methanol and the reaction mixture was poured onto ice. It was taken up in ether, washed 3 times with saturated NH ₄ Cl and then neutralized with brine. After drying over Na ₂ SO _4, it was filtered, concentrated and after distillation using a Vigreux column (boiling point: 100 ° C. at 5 × 10 ² Pa).
265.4 g of a colorless oil were obtained, representing a theoretical yield of 96%.
IR: 2930, 1600, 1495, 1460, 1390, 1190, 1110, 970 cm ^-1
NMR ⁽¹ H): 0.88 (d, J = 7.6Hz, 3H); 2.02 (m, 1H); 2.39 (dd, J = 8 and 16 Hz, 1H); 2.76 (dd, J = 8 and 16Hz, 1H); 3.02 (m, 2H); 3.33 (s, 3H); 7.21 (m, 5H)
NMR ( ¹³ C): 140.7 (s); 129.2 (d); 128.2 (d); 125.8 (d); 77.5 (t); 58.7 (q); 39.9 (t); 35.4 (d); 16.8 (q)
SM: 164 (4, M ⁺ ), 132 (64), 117 (100), 91 (89), 65 (18), 45 (37)

Example 2 Synthesis of 1- (2-methoxypropyl) -4-methylbenzene a) 1- (2-hydroxypropyl) -4-methylbenzene

In a 2.5 l reactor, the magnesium of bromotoluene was prepared from 400 g of bromotoluene and 63 g of magnesium. To this magnesium was added at room temperature 150 g of propylene oxide in 20 minutes. After one hour at this temperature, it was hydrolyzed with one liter of a 4M hydrochloric acid solution. The product was extracted with ether, and this organic phase was washed several times until neutral, then dried over MgSO ₄ . This crude product was distilled on a column to provide 320 g of desired alcohol (91%).
NMR ⁽¹ H): 1.23 (d, J = 6Hz, 3H); 1.61 (s, 0H); 2.32 (s, 3H); 2.64 (dd, J = 13 and 8 Hz, 1H); 2.74 (dd, J = 13 and 5 Hz); 3.97 (m, 1H); 7.10 (m, 4H)
NMR ( ¹³ C): 21.01 (q); 22.73 (q); 45.36 (t); 68.89 (d); 129.24 (2d); 129.29 (2d); 135.42 (s); 135.96 (s)
SM: 150 (9, M ⁺ ), 135 (4), 117 (4), 115 (5), 106 (100), 91 (74), 79 (8), 77 (12), 45 (7)

b) 1- (2-methoxypropyl) -4-methylbenzene

190 g of 1- (2-hydroxypropyl) -4-methylbenzene were added dropwise, in a 2.5 L flask, to 51 g of 60% sodium hydride in 400 ml of THF. The temperature was maintained around 0 ° C by an ice bath. After one hour, 270 g of methyl iodide dissolved in 200 ml of THF were added and the reaction was left for another hour at room temperature. It was then hydrolyzed with a 4M solution of hydrochloric acid. The product was then extracted with ether and the organic phase was washed until neutral. After drying, the crude product was distilled (approximately 90 ° C. at 14 × 10 ² Pa), to obtain 173 g (83%) of pure product.
NMR ( ¹ H): 1.10 (d, J = 5.3 H); 2.30 (s, 3H); 2.56 (dd, J = 14 and 7 Hz, 1H); 2.88 (dd, J = 14 and 6 Hz, 1H); 3.32 (s, 3H); 3.50 (m); 7.08 (s, 4H)
NMR ( ¹³ C): 18.87 (q); 21.00 (q); 42.28 (t); 56.22 (q); 78.17 (d); 128.94 (d); 129.29 (d); 135.49 (s); 135.90 (s)
SM: 164 (12, M ⁺ ), 149 (2), 133 (2), 117 (5), 115 (6), 106 (21), 105 (28), 91 (10), 77 (12), 59 (100).

Example 3 Synthesis of 3-methoxy-2,2,3-trimethyl-1-phenylbutane a) 2,3,3-trimethyl-4-phenyl-2-butanol

A solution of methyl iodide magnesium was prepared from 21.7 g of methyl iodide, 3.4 g of magnesium and 80 ml of diethyl ether in a three-necked flask equipped with a condenser, a thermometer and '' a bulb to introduce and under a nitrogen atmosphere. A solution of 3,3-dimethyl-4-phenyl-2-butanone (prepared according to the recipe described in application DE 3210725) was then added in 70 ml of diethyl ether, leaving to react under reflux. The reaction mixture was stirred at room temperature overnight, then poured onto ice, washed to neutrality with a saturated NH ₄ Cl solution and dried over MgSO ₄ . The solution was concentrated in vacuo and distilled on a Vigreux type column at 41-55 ° / 1.2x10 ¹ Pa, to obtain 17.0 g (62%) of the desired product.
IR: 3464.2973, 1496, 1375, 1128, 1099 cm ^-1
1 H-NMR: 0.84 (s, 6H), 1.29 (s, 6H), 2.68 (s, 2H), 7.11-7.30 (m, 5H)
¹³ C-NMR: 139.6 (s), 131.1 (2d), 127.6 (d), 125.8 (d), 76.7 (s), 42.3 (t), 41.2 (s), 25.53 (q), 25.48 (q), 21.4 (2q)
MS: 192 (0, M ⁺ ), 134 (26), 91 (52), 59 (100), 43 (18).

b) 3-methoxy-2,2,3-trimethyl-1-phenylbutane

This compound was prepared in a manner analogous to that described in 1b) from the alcohol prepared previously (12 g, 0.048 mole), 10.4 ml of a suspension of KH at 20% in oil ( 0.06 mole) and 8.74 g (0.062 mole) of methyl iodide, and 70 ml of THF. 10.1 g of a product having a boiling point of 56 ° / 1.2 × 10 ¹ Pa were thus obtained. A product with a purity of 99% can be obtained by subjecting this distillation product to chromatography on an SiO ₂ column using a cyclohexane / diethyl ether mixture as eluent.
IR: 2973, 2824, 1472, 1364, 1153, 1075 cm ^-1
1 H-NMR: 0.79 (s, 6H), 1.18 (s, 6H), 2.68 (s, 2H), 3.23 (s, 3H), 7.11-7.30 (m , 5H)
¹³ C-NMR: 140.2 (s), 131.3 (2d), 127.4 (2d), 79 (s), 49.4 (q), 42 (t), 41.7 (s), 21.5 (2q), 19.3 (2q)
MS: 206 (0, M ⁺ ), 91 (20), 73 (100), 43 (12).

Example 4 Stability test of 1-methoxy-2-methyl-3-phenylpropane and 1- (2-methoxypropyl) -4-methylbenzene in bleach

A = odeur non changée

B = odeur légèrement modifiée

C = changement assez net

D = très fort changement, devient déplaisant

E = totalement modifié, non reconnaissable

et l'intensité de l'odeur étant signifiée dans une échelle croissante de 1 à 10. Produit Températures 3°C 22°C 40°C 1-méthoxy-2-méthyl-3-phénylpropane A8 A7 B6 1-(2-méthoxypropyl)-4-méthylbenzène A8 A6 B5 The products mentioned above were diluted to 0.2% in unscented bleach and stored for 30 days at temperatures of 3 °, 22 ° and 40 ° C.
The items thus stored were then evaluated for the quality of their odor by expert perfumers.
The value of the resulting olfactory quality is given in the following table by the letters A to E having the meanings

A = odor not changed

B = slightly modified odor

C = fairly clear change

D = very strong change, becomes unpleasant

E = totally modified, not recognizable

and the intensity of the odor being signified on an increasing scale from 1 to 10. Product temperatures 3 ° C 22 ° C 40 ° C 1-methoxy-2-methyl-3-phenylpropane AT 8 A7 B6 1- (2-methoxypropyl) -4-methylbenzene AT 8 A6 B5

The results show that the two compounds according to the invention have a excellent stability in bleach. Furthermore, the quality and power of their olfactory notes have proven to be excellent for covering the bad smell of bleach.

Example 5 Ylang type perfume composition for use in a detergent

ingredients Parts by weight Linalyl acetate 20 Verdyl acetate 80 Methyl benzoate 20 Cetalox® at 10% 10 citronellol 120 Dihydromyrcenol 170 eugenol 20 geraniol 200 Habanolide® 200 Indol at 10% 20 Iralia® 100 Phenoxyethyl isobutyrate 20 Lorysia® 200 Mayol® 30 Methyl-para-cresol 10 Phénylhexanol 230 4-tert-Butyl-1-cyclohexanol 50 Total 1500 By adding 50 parts of 1-methoxy-2-methyl-3-phenylpropane to this floral base composition, it is given a softer and sophisticated note. In addition, we observe that the medicinal side of methyl para-cresol is cut by a pretty pink and fruity olfactory touch, also slightly green, very noticeable.

Example 6 Perfuming composition for use in bleach

ingredients Parts by weight Camphor 150 Dodécanitrile 80 dihydroterpineol 70 diphenyl 600 eucalyptol 450 3,7-dimethyl-3-octanol 750 Total 2100

When added to this typical base composition for bleach 16% by weight of 1-methoxy-2-methyl-3-phenylpropane, it is found that its odor acquires a superb flowery-pink character, very natural. We also notice the fading of the medicinal effect conferred by eucalyptus, as well as the metallic note of diphenyloxide, so that the smell of the composition softens, the compound of the invention bringing it a nice fruity sub-note.

Claims (7)

1. Use as perfuming ingredient of 1-methoxy-2-methyl-3-phenylpropane, 1-(2-methoxy-propyl)-4-methylbenzene or 3-methoxy-2,2,3-trimethyl-1-phenylbutane.
2. Perfuming composition or perfumed article containing as perfuming ingredient 1-methoxy-2-methyl-3-phenylpropane, 1-(2-methoxypropyl)-4-methyl-benzene and/or 3-methoxy-2,2,3-trimethyl-1-phenylbutane.
3. Perfumed article according to claim 2, in the form of a perfume or cologne, a soap, a bath or shower gel, a shampoo or other hair care product, a cosmetic preparation, a body deodorant or an air freshener, a detergent or a fabric softener, or an all-purpose cleaner.
4. Detergent or chlorinated product containing as perfuming ingredient 1-methoxy-2-methyl-3-phenylpropane, 1-(2-methoxypropyl)-4-methylbenzene and/or 3-methoxy-2,2,3-trimethyl-1-phenylbutane.
5. Article according to claim 3 or 4, characterized in that the detergent is a detergent having an aggressive medium and/or having a high pH-value, in particular chlorine bleach.
6. 1-(2-Methoxypropyl)-4-methylbenzene.
7. 3-Methoxy-2,2,3-trimethyl-1-phenylbutane.