DE4125765A1 - TRIMETHYLHEXANAL DERIVATIVES, THEIR PRODUCTION AND USE - Google Patents

Abstract

The invention concerns trimethylhexanal derivatives of general formula (I), in which R<1> and R<2>, independently of each other, are an alkyl group with 1 to 3 C-atoms and R<3> is an alkyl, acyl or alkoxycarbonyl group with 1 to 3 C-atoms. These compounds possess scent characteristics with complex sandalwood and green notes and high diffusion power and can be mixed in widely varying proportions with each other and with other odiferous substances to give new scent compositions, generally containing 1 to 70 % by wt. relative to the total composition. These compositions can be used to scent cosmetic preparations and industrial products, as well as in alcohol-based fragrances.

Description

The invention relates to new trimethylhexanal derivatives, a process for their production and their use as fragrances.

Many natural fragrances are available in completely inadequate amounts, measured by their needs. For example, 5000 kg rose petals are required to produce 1 kg of rose oil; the consequences are a very limited world annual production and a high price. It is therefore clear that the fragrance industry has a constant need for new fragrances with interesting fragrances to complement the range of naturally available fragrances and make the necessary adjustments to changing modern tastes and the ever increasing need for odor improvers for everyday products how to cover cosmetics and detergents.

In addition, there is generally a constant need for synthetic Fragrance substances that are cheap and of constant quality len and have desired olfactory properties, d. H. attached take odor profiles that are as close to nature as possible and qualitatively new possess sufficient intensity and are able to smell kos to influence metallic and consumer goods advantageous. It was therefore searched for compounds that add characteristic new odor profiles high adhesive strength, smell intensity and radiance at the same time should point.

It has now been found that the compounds of the general formula (I) meet this requirement in every respect and is an advantage as fragrances with differently nuanced odor notes can be used with good adhesive strength.  

The subject of the invention are therefore trimethylhexanal derivatives of the general Formula (I),

wherein the radicals R¹ and R² independently of one another are an alkyl group with 1 up to 3 carbon atoms and R³ is an alkyl, acyl or alkoxycarbonyl group with 1 mean up to 3 carbon atoms.

Those compounds of the general formula (I) according to the invention in which the radicals R ¹ and R ² independently of one another stand for an alkyl group having 1 to 2 carbon atoms are particularly preferred. Those compounds in which R ^{3 is} an alkoxycarbonyl radical are very particularly preferred.

Another object of the invention is a process for the preparation of trimethylhexanal derivatives of the general formula (I), wherein R ¹ , R ² and R ^{3 have} the meaning given above, by dehydrating base-catalyzed aldol condensation of 3,5,5-trimethylhexanal with the with the corresponding short-chain aliphatic ketones, the reduction of which, for. B. with complex hydrides or by the method of Meerwein-Ponndorf with aluminum alcoholates to the corresponding alcohols and finally their derivatization to the corresponding esters (Ia), carbonates (Ib) or allyl ethers (Ic).

The new compounds (I) are prepared in accordance with known methods Synthetic methods of organic chemistry. Com serves as the starting material Commercially available 3,5,5-trimethylhexanal, which is practiced in the presence Licher catalysts with corresponding short-chain ketones, for. B. 2-Bu can implement tanone or 3-pentanone in a mixed aldol condensation, taking intermediate aldol condensation products with elimination of water directly the corresponding α, β unsaturated aldol condensation products (Z1) can be obtained. The reaction is expediently carried out with a  Excess of the more reactive and volatile component. As Catalysts come e.g. B. sodium hydroxide, sodium methoxide, sodium amide, Potassium tert-butoxide or heterogeneous catalysts such as potassium fluoride Alumina in question.

The carbonyl function of the aldol condensation products (Z1) can be found in ei reduce ner further reaction to the OH group, e.g. B. by means of complex Hydrides such as lithium aluminum hydride or lithium or sodium borohydride. In this way the alcohols (Z2) are obtained.

The alcohols (Z2) are then esterified with short-chain Carboxylic acids in the esters (Ia) or by reaction with z. B. dimethyl or Diethyl carbonate in the carbonates (Ib) or by etherification Williamson, if desired in the presence of a phase transfer catalyst tors, into the allyl ether (Ic) transferred.

The compounds (I) can then by conventional methods, for. B. can be purified by distillation.  

The compounds (I) according to the invention have remarkable Ge olfactory properties, such as are very sought after in the fragrance industry, namely sandalwood or green with very complex shades and great charisma. The compounds of type (Ia) by their sandal scent, while the compounds of type (Ib) show fresh green notes.

Another object of the invention is therefore the use of Ver Bonds of the general formula (I) as fragrances.

Sandalwood oil is particularly valued and worthy from a perfume point of view full. It is made by steam distillation from the heartwood of sandalwood delights, a tropical semi-parasite that occurs in India and Malaysia is coming. Heartwood appears after about ten years and only starts at twenty year old trees to train faster. Fully grown trees are cleared at the age of 30 to 60 years because the roots are special are rich in fragrant heartwood (see E. T. Morris, Dragoco Report 1983 (30) 40). It is therefore understandable that fragrance research constantly strives to find suitable substitutes for natural sandalwood oil develop.

Substituted mono-, bi- or tricyclic systems represent the large number of fragrances with a deluxe wood scent known from the prior art. This also applies to α- and β-santalol, the main constituents of natural sandalwood oil. The applicant is only aware of one example of a commercially available non-cyclic sandal fragrance which is marketed under the trade name Osyrol ^(TR) and which is a 2,6-dimethyl 2-methoxy-6-hydroxy-octane (US Pat. No. 3,963,648). In the Japanese patent application JP 90/2 82 339 non-cyclic alcohols with a smell of sand, for. B. tetramethyldecan-4-en-3-ol.

German patent application DE 32 45 047 describes aliphatic alcohols and esters, the fruity and in particular pear-like scents or Ambrette-woody, floral and balsamic fragrances. Especially 5,7,7-Trimethyloctylpropionate is emphasized, its fruity, bir special note is emphasized.  

The odor profile of the compounds (I) is original and novel. In Perfume compositions strengthen the connections (I) and harmony Radiance as well as liability, taking the dosage under consideration inspection of the other components of the composition to the respective aspired fragrance is tuned.

That the trimethylhexanal derivatives (Ia) Sandel notes or the derivatives (Ib) Showing green notes was not predictable and is therefore another Confirmation of the general experience that the olfactory Eigen known odoriferous substances do not have any compelling conclusions about the egg properties of structurally related connections, because neither the Me mechanism of fragrance perception still influences the chemical structure the fragrance perception has been sufficiently researched, so normally can not be predicted whether a modified structure is known Fragrances lead to a change in the olfactory properties and whether these changes are judged positively or negatively.

The compounds of formula (I) are suitable due to their odor profile especially for the modification and reinforcement of known composites their extraordinary ge strong smell, which generally contributes to the refinement of the composition.

The compounds of the formula (I) can be prepared using numerous known methods Fragrance ingredients, e.g. B. other fragrances natural, synthe table or partially synthetic origin, essential oils and plants Combine zen extracts. The range of natural fragrances can both light and medium and low volatile components and that of synthetic fragrances representatives from practically all Include substance classes. Examples are:

• a) Natural products such as tree moss absolute, basil oil, agricultural oils such as Bergamot oil, mandarin oil, etc., mastic absolute, myrtle oil, Palmarosa oil, patchouli oil, petitgrain oil, wormwood oil, myrrh oil, olibanum oil
• b) alcohols such as farnesol, geraniol, linalool, nerol, phenylethyl alcohol, Rhodinol, cinnamon alcohol, Sandalore [3-methyl-5- (2,2,3-trimethylcyclo pent-3-en-1-yl) pentan-2-ol], Sandela [3-isocamphyl- (5) -cyclohexanol],  
• c) Aldehydes such as Citral, Helional®, α-hexylcinnamaldehyde, hydroxycitronel lal, Lilial® [p-tert-butyl-α-methyldihydrocinnamaldehyde], methyl nonyl acetaldehyde,
• d) ketones such as allyl ionone, α-ionone, β-ionone, isoraldein, methyl ionone,
• e) esters such as allylphenoxyacetate, benzyl salicylate, cinnamyl propionate, Citronellyl acetate, citronellyl ethoxylate, decyl acetate, dimethylbenzyl carbinyl acetate, ethyl acetoacetate, hexenyl isobutyrate, linalyl acetate, Methyl dihydrojasmonate, vetiveryl acetate, cyclohexyl salicylate
• f) lactones such as τ-undecalactone, 1-oxaspiro [4,4] nonan-2-one,

as well as various other components often used in perfumery such as Ketone musk, indole, p-menthan-8-thiol-3-one, methyleugenol, ambroxan.

It is also remarkable how the connections of the Structure (I), especially (Ia), the olfactory notes of a wide range Round off well-known compositions and harmonize, but without being unpleasant dominant way.

Some of the compounds according to the invention contain centers of chirality, see above that these connections can exist in different spatial forms. in the In the context of conventional syntheses, the compounds according to the invention are considered Mixtures of the corresponding isomers and are as such as olfactory fabrics used.

The usable proportions of the compounds according to the invention or their Mixtures in fragrance compositions range from 1 to 70 weights percent, based on the total mixture. Mixtures of the invention Compounds (I) and compositions of this type can be used both for perfume lubrication of cosmetic preparations such as lotions, creams, shampoos, soaps, Ointments, powders, aerosols, toothpastes, mouthwashes, deodorants as well alcoholic perfumery (e.g. Eaux de Cologne, Eaux de Toilette, Ex traits) can be used. There is also an application for par filling technical products such as washing and cleaning agents, fabric softener and textile treatment agents or tobacco. To perfume this ver different products, these are the compositions in an olfactory effective amount, especially in a concentration of 0.05 to 2 Ge percent by weight, based on the entire product, added. These values  However, should not represent limit values, since the experienced perfumer too achieve effects with even lower concentrations or with still higher doses can build up new complexes.

The following examples are intended to explain the subject matter of the invention and are not to be interpreted as restrictive.  

Examples 1. Preparation of the preliminary stages a) 4,7,9,9-tetramethyl-4-decen-3-one

In a 250 ml three-necked flask, 46.5 g of 3,5,5-trimethylhexanal (Hoechst) were mixed with 140.1 g of diethyl ketone (3-pentanone) and 40 g of aluminum oxide / potassium fluoride (prepared by Suspend 20 g of Al ₂ O ₃ in 40 g of 50% aqueous KF solution and then concentrate to constant weight). The mixture was stirred at 60 ° C for 4 hours and at 90 ° C for 6 hours. The starting aldehyde was then completely converted. The catalyst was filtered off, the filtrate was distilled on a Rotavapor and then on a Vigreux column in a high vacuum. 53 g of crude product were obtained. The fine distillation gave 30.1 g of the product with a boiling point of 77-80 ° C / 0.02 mbar and a purity of 90% determined by gas chromatography.

b) 4,7,9,9-tetramethyl-4-decen-3-ol

5 g of sodium borohydride in 100 ml were placed in a 250 ml three-necked flask Ethanol suspended. 29.3 g of 4,7,9,9-tetramethyl-4-decen-3-one were dissolved in 80 ml of ethanol dissolved and continuously to the stirred suspension in 15 Minutes dosed. The temperature of the reaction mixture rose about 30 ° C. The mixture was then refluxed for 20 minutes heated. After cooling, the mixture was poured onto a saturated one for working up Ammonium chloride solution / ice mixture and extracted several times with ether. The combined organic phases were washed neutral with water, over Potassium carbonate dried and concentrated. The subsequent Kugelrohrde Stillation in a high vacuum at 0.08 mbar and an air bath temperature of 150 ° C delivered 23.8 g of crude product, which was released by a rotary distillation was cleaned. The main run of 18.6 g went at a head temperature of 71-75 ° C / 0.02 mbar above.  

2. Preparation of the compounds I according to the invention 2.1. Type (Ia) compounds Example 1 4,7,9,9-tetramethyl-4-decen-3-yl formate

A solution of 30 g of 4,7,9,9 tetramethyl-4-decen-3-ol in 32 g of 99% formic acid was stirred into a 250 ml three-necked flask at room temperature. A further 20 g of formic acid were then added to the mixture and the mixture was stirred again at room temperature for 16 hours. The excess of formic acid was distilled off in a water jet vacuum and the residue was fractionally distilled on a rotating column. The main run of 7.1 g of the ester went under a high vacuum at 0.02 mbar and a head temperature of 82-85 ° C. The gas chromatographic content of the desired compound was approximately 90%. The IR spectrum (film on NaCl) showed adsorption bands at 2954, 1728 (ester CO band), 1364 and 1169 cm ^-1 (CO vibration).

Smell: fruity, woody, balsamic, sandal note.

2.2. Type (Ib) compounds Example 2 4,7,9,9-tetramethyl-4-decen-3-yl-ethyl carbonate

In a 250 ml three-necked flask with Dean-Starck water separator attachment, 31.9 g of 4,7,9,9-tetramethyl-4-decen-3-ol were mixed with 62 g of diethyl carbonate and 3 g of sodium methoxide (30% in methanol ) added. The mixture is heated to 90 ° C. with stirring and the ethanol formed in the course of the reaction is distilled off via the water separator. To remove the catalyst, the mixture is washed twice with sodium sulfate solution. After the water phase had been separated off, the organic phase was transferred to a still and the excess diethyl carbonate was removed by distillation. Distillation of the residue over a 30 cm Vigreux column gave 14 g of the product with a GC purity of 95.3% at a top temperature of 92-93 ° C / 0.05 mbar. The IR spectrum (film on NaCl) shows bands at 2954, 1745 (carbonate-C = O), 1369 and 1258 cm ^-1 (CO vibrations).

Smell: very natural note of freshly cut grass  

Composition example

Odor characteristic: floral (rose)

The addition of 10 parts of compound Ib (from Example 2) has an effect more harmonious, uniform smell, the natural rose fragrance comes closer than the original composition.

Claims (7)

1. Trimethylhexanal derivatives of the general formula (I) wherein the radicals R¹ and R² independently of one another are an alkyl group with 1 to 3 C atoms and R³ is an alkyl, acyl or alkoxycarbonyl group with 1 to 3 C atoms. 2. Trimethylhexanal derivatives according to claim 1, wherein the radicals R ¹ and R ^{2 are} independently an alkyl group having 1 to 2 carbon atoms. 3. trimethylhexanal derivatives according to claim 1 or 2, wherein the radical R ^{3 is} an alkoxycarbonyl radical. 4. Process for the preparation of trimethylhexanal derivatives of the general formula (I), wherein the radicals R ¹ and R ² independently of one another are an alkyl group having 1 to 3 C atoms and R ^{3 is} an alkyl, acyl or alkoxycarbonyl group having 1 to 3 C atoms, by dehydrating base-catalyzed aldol condensation of 3.5.5 -Trimethylhexanal with the corresponding short-chain aliphatic ketones, the reduction of which, for. B. with complex hydrides to the corresponding alcohols and finally their derivatization to the corresponding esters (Ia), carbonates (Ib) or allyl ethers (Ic). 5. Use of trimethylhexanal derivatives according to one of claims 1 up to 4 as fragrances. 6. Fragrance compositions containing a trimethylhexanal Derivative of the formula (I) according to Claims 1 to 4 in an amount of 1-70% by weight, based on the entire composition. 7. Use of mixtures of trimethylhexanal derivatives of the formula I. according to claims 1 to 4 as fragrances in cosmetic preparations, technical products or alcoholic perfumery.