DE4203790A1 - BUTENOL DERIVATIVES, THEIR PREPARATION AND USE - Google Patents

Abstract

The invention concerns butenol derivatives of general formula (I), in which R<1> is hydrogen or an alkyl group with 1 to 4 C-atoms and R<2> is an alkyl group with 1 to 4 C-atoms, with the provision that R<2> is not a methyl group if R<1> is a methyl group. These compounds are odiforous substances with interesting fragrances and considerable diffusion power.

Description

Field of the invention

The invention relates to novel butenol derivatives, a process for their preparation position and their use as fragrances.

State of the art

Many natural fragrances are completely inadequate in terms of demand available quantity. Especially appreciated from a perfumist point of view and valuable is the sandalwood oil. It is made by steam distillation extracted from the heartwood of sandalwood, a tropical semi-parasite, which occurs in India and Malaysia. Heartwood appears after about ten Years and begins only at twenty-year-old trees, faster form. Fully grown trees become between the ages of 30 to 60 years The roots are especially rich in fragrant heartwood [Comp. E.T. Morris, Dragoco Report 1983 (30), 40]. It is therefore understandable Lich, that fragrance research is constantly endeavoring to find suitable substitutes to develop natural sandalwood oil.

The emphasis in the development of suitable substitutes for natural Sandalwood oil has R.E. Naipawer outlined in a review [in: B.M. Lawrence, B. D. Mookherjee, B.J. Willis (ed.): "Flavors and Fragrances: A World Per spective "; Elsevier Publishers, Amsterdam 1988]. From the European Pa EP 1 55 591 B1, alcohols having a 2,2,3- Trimethyl-3-cyclopentenyl known. However, this group contains one Side chain which is either saturated or has a double bond in α, β- Position has.  

US Pat. No. 4,052,341 has disclosed 3-methyl-5- (2,2,3-trimethyl-3-cyclopentene) 1-yl) pentan-2-ol to the subject. This alcohol is in Table I. (Columns 3 and 4 of the US Patent) certain analogues, isomers and Faced with homologs; Of these compounds, seven have one saturated side chain and one compound, namely 3-methyl -5- (2,2,3-trimethyl-3-cyclopenten-1-yl) -3-penten-2-ol, an unsaturated one Side chain. In the description, the superior effect of 3- Methyl 5- (2,2,3-trimethyl-3-cyclopenten-1-yl) -pentan-2-ol with respect to Odor intensity compared to the other compounds of Table I forth issued (column 4).

From the context outlined it is therefore clear that the fragrance industry a constant need for new fragrances with interesting Fragrance notes has to add to the range of naturally available fragrances too complement and make the necessary adjustments to changing fashionable Ge flavors and the ever increasing demand for Ge odor improvers for everyday products such as cosmetics and cosmetics To cover cleaning agents.

In addition, there is a general need for synthetic Fragrances that are cheap and of consistent quality and have desirable olfactory properties, i. H. is take as natural as possible and qualitatively novel smell profiles of possess sufficient intensity and are able to smell the scent of kos to positively influence both physical and consumer goods. It was therefore looking for compounds that add characteristic new odor profiles at the same time high adhesion, odor intensity and radiance should point.

Description of the invention

It has now been found that the compounds of general formula (I) the meet the above requirements perfectly in every respect and in advantageous as fragrances with different nuanced Ge odoriferous with good adhesion can be used.  

The present invention therefore relates to butenol derivatives of general formula (I),

wherein the radical R ^{1 is} hydrogen or an alkyl group having 1 to 4 C atoms and the radical R ^{2 is} an alkyl group having 1 to 4 C atoms, wherein R ^{2 is} the meaning of a methyl group except if R ¹ is a methyl group ,

Particular preference is given to those compounds of the general formula (I) according to the invention in which the radical R ^{1 is} hydrogen, methyl or ethyl and the radical R ^{2 is} methyl, ethyl, propyl or isopropyl. Quite particularly preferred are 4-methyl-6- (2,2,3-trimethyl-3-cyclopenten-1-yl) -4-hexen-3-ol, 4-ethyl-6- (2,2,3- trimethyl-3-cyclopenten-1-yl) -4-hexen-3-ol and 2,4-dimethyl-6- (2,2,3-trimethyl-3-cyclopenten-1-yl) 4-hexene-3 oil.

Another object of the invention is a process for the preparation of butenol derivatives of the general formula (I) wherein R ¹ and R ^{2 have} the abovementioned meaning, by condensation of α-campholenaldehyde with the corresponding aldehydes or ketones to the corresponding unsaturated Carbonyl compounds and subsequent reduction of the Carbonylfunk tion of these compounds z. B. with complex hydrides for OH function.

The preparation of the novel compounds (I) takes place according to known per se Synthetic method of organic chemistry. The starting material used is α- Campholenaldehyde, which in the presence of conventional catalysts with ent short-chain aldehydes and ketones, for example 2-butanone or 3-pentanone in a mixed aldol condensation, wherein via intermediate aldol condensation products with elimination of water directly obtained the corresponding α, β-unsaturated aldol condensation products become. Conveniently, the reaction is carried out with an excess of  more reactive and volatile components. As catalysts For example, sodium hydroxide, sodium methoxide, sodium amide, Ka lium tert-butoxide or heterogeneous catalysts such as potassium fluoride on Alumina in question. The carbonyl function of the aldol condensation products can be reduced in a further reaction to the OH group, for example using complex hydrides such as lithium aluminum hydride or lithium or sodium borohydride. In this way, the butenol derivatives of the general formula (I). The compounds (I) can subsequently be purified by conventional methods, for example by distillation.

The compounds (I) according to the invention have remarkable Ge ruchseigenschaften. Another object of the invention is therefore the Use of the compounds of the general formula (I) as fragrances.

In this case, the compounds (I) and in particular 4-methyl-6 are characterized (2,2,3-trimethyl-3-cyclopenten-1-yl) -4-hexen-3-ol by their Sandelgeruch with very complex shades and great charisma.

The odor profile of the compounds (I) is opposite to the cited state the technique original and novel. In addition, the odor inks sity of the compounds (I) higher than that of the closest prior art Technology; for the proof of the improved odor intensity is on the Determination of the odor thresholds referenced in the examples section.

In perfume compositions, the compounds (I) enhance harmony and harmony Radiation as well as the adhesion, whereby the dosage under Berück the composition of the remaining parts of the composition aspired scent is tuned.

That the butenol derivatives (I) have Sandel notes was not foreseen and is thus further confirmation of the general experience that the olfactory properties of known fragrances do not force one conclusions about the properties of structurally related compounds because neither the mechanism of scent perception nor the influence The chemical structure of the fragrance perception sufficiently explored are, so therefore normally can not be foreseen, whether a  changed structure of known fragrances ever to change the olfak Toric properties and whether these changes are positive or negative be assessed.

The compounds of the formula (I) are suitable because of their odor profile in particular also for the modification and reinforcement of known composites tions. Particular emphasis should be placed on their extraordinary gifts ruchsstärke, which generally contributes to the refinement of the composition.

The compounds of formula (I) can be with many known Fragrance ingredients, e.g. B. other fragrances natural, synthe tables or partial synthetic origin, essential oils and Pflan combine zene extracts. The range of natural fragrances can Both light and medium and low volatility components and that of the synthetic fragrances representatives from virtually all Include substance classes. Examples are:

• a) Natural products such as tree moss absolute, basil oil, citrus 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, cinnamyl 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 ^R , α-hexylcinnamaldehyde, hydroxycitronelium, Lilial ^R [p-tert-butyl-α-methyldihydrocinnamaldehyde], methylnonylacetaldehyde,
• d) ketones such as allylionone, α-ionone, β-ionone, isoraldein, methylionone,
• e) esters such as allylphenoxyacetate, benzylsalicylate, cinnamylpropionate, Ci tronellyl acetate, citronellyl ethoxylate, decyl acetate, dimethylbenzyl carbinyl acetate, ethyl acetoacetate, hexenyl isobutyrate, linalyl acetate, Methyl dihydrojasmonate, vetiveryl acetate, cyclohexyl salicylate
• g) lactones such as gamma undecalactone, 1-oxaspiro [4.4] nonan-2-one, as well as various other often used in perfumery components such as Ketone musk, indole, p-menthane-8-thiol-3-one, methyleugenol, ambroxan.

Also noteworthy is the way in which the connections of the Structure (I) the odor notes of a wide range of known com  round off and harmonize positions without, however, becoming unpleasant dominate. 4-methyl-6- (2,2,3-trimethyl-3-cyclopentenyl) -4-hexen-3-ol To emphasize in this regard particularly.

The compounds of the invention contain chiral centers, so that These compounds can exist in different spatial forms. In the yard men usual syntheses fall the connections according to invention as Ge mix the corresponding isomers and are as such as olfactory used substances.

The usable proportions of the compounds of the invention or their Mixtures in fragrance compositions range from 1 to 70 weight percent, based on the total mixture. Mixtures of the invention Compounds (I) as well as compositions of this kind can be used both for perfuming cosmetic products such as lotions, creams, shampoos, soaps, Ointments, powders, aerosols, toothpastes, mouthwashes, deodorants as well alcoholic perfumery (eg Eaux de Cologne, Eaux de Toilette, ex traits). There is also a possibility to use the par fümierung technical products such as detergents and cleaning agents, softening ler and textile treatment or tobacco. For perfuming this ver various products become these the compositions in an olfactory effective amount, in particular in a concentration of 0.05 to 2 Ge percent by weight, based on the total product. These values However, should not represent limits, as the experienced perfumer also achieve effects with even lower concentrations or even with higher doses can build novel complexes.

The following examples are intended to illustrate the subject matter of the invention and are not meant to be limiting.

Examples 1. Preparation of the precursors for the compounds of the invention Example 1: 4-Methyl-6- (2,2,3-trimethyl-3-cyclopenten-1-yl) -4-hexen-3-one

In a 2 L three-necked flask, 243 g (1.6 mol) of α-campholenaldehyde were mixed with 688 g (8 mol) of diethyl ketone under a nitrogen atmosphere. While cooling with an ice bath and stirring, 64 g of sodium methylate solution (30% strength in methanol) were added continuously within 45 minutes at an internal temperature of 30 ° C. After the addition, the reaction mixture was stirred for a further 5 hours at room temperature and allowed to stand overnight. For workup, the excess of diethyl ketone was distilled off, the residue taken up in 200 ml of ether and carefully neutralized with 10% hydrochloric acid. The organic phase was separated and washed three times with saturated brine. After drying over sodium sulfate, the mixture was filtered and concentrated on a rotary evaporator. The residue of 435 g of reaction mixture was purified by distillation through a 12 cm Vigreux column. The main fraction passed at 90-93 ° C / 0.03 mbar. It was a purity of 95% (GC) he goes. The IR spectrum (film on NaCl) showed characteristic absorption bands at 2954, 1670 (unspiked ketone), 1381 and 1360 (according to methyl groups) and at 798 cm ^-1 . Odor: slightly floral, rose, spicy, woody.

Example 2: 2-Ethyl-4- (2,2,3-trimethyl-3-cyclopenten-1-yl) -2-butene-1-al

In a 1 l three-necked flask equipped with KPG stirrer, internal thermometer and reflux condenser 152 g (1 mol) of α-Campholenaldehyd were mixed at room temperature with 216 g of n-butyraldehyde under nitrogen atmosphere and stirring. The reaction vessel was cooled in an ice-water bath and then 54 g (0.3 mol) of sodium methoxide (30% in methanol) with vigorous stirring ren within one hour continuously added; The temperature of the reaction mixture at the beginning of the addition of the sodium methoxide increased to 75 ° C. as a result of the onset of the exothermic reaction. The reaction mixture was then stirred for a further 5 hours at 5 ° C and then allowed to stand overnight. For work-up, it was carefully neutralized with acetic acid and washed 3 times with 200 ml of water each time. The organic phase was diluted with ether, dried over sodium sulfate, filtered off and freed from ether and excess butyraldehyde on a rotary evaporator. The resulting residue (490 g) was distilled through a 12 cm Vigreux column under high vacuum (0.15 mbar) to give 215 g of the main fraction (boiling point 100 ° C., purity 78% according to GC), which was further fractionated on a rotating-band column was purified (GC purity: 97.4%). The IR spectrum (film on NaCl) showed characteristic absorption bands at 2956, 2708, 1690, 1641, 1361, 1329 and 799 cm ^-1 . Odor: fresh woody, fruity, Jonon note.

2. Preparation of the compounds of the invention Example 3: 4-Methyl-6- (2,2,3-trimethyl-3-cyclopenten-1-yl) -4-hexen-3-ol

In a 250 ml three-necked flask, 1 g of sodium borohydride was suspended in 50 ml of ethanol and 22.0 g of 4-methyl-6- (2,2,3-trimethyl-3-cyclopenten-1-yl) -4-hexen-3-one (Example 1) was added dropwise at room temperature continuously. After the weakly exothermic reaction has subsided, stirring was continued for one hour, the mixture was poured onto ammonium chloride / ice and extracted with ether. The organic phases were dried over sodium sulfate, filtered and concentrated. The distillation over a short Vigreux column and then ßend on a rotary belt distillery supplied 15 g main run with a boiling point of 108-110 ° C / 0.1 mbar with a GC purity of 98.4%. The IR spectrum (film on NaCl) showed bands at 3358 (-OH), 2955, 1381 and 1359 (according to dimethyl) and 1011 (CO) cm ^-1 .

Smell: strong sandal and musk notes, fruity, green.

Example 4: 3-Ethyl-5- (2,2,3-trimethyl-3-cyclopenten-1-yl) -3-penten-2-ol

To a stirred slurry of 11.2 g (0.46 mol) of magnesium turnings in 100 ml of anhydrous ether were added under exclusion of moisture 64.8 g (0.46 mol) methyl iodide was added dropwise. To the solution of methylma thus prepared magnesium iodide were added with moisture exclusion and nitrogen atmosphere 72 g (0.35 mol) of 2-ethyl-4- (2,2,3-trimethyl-3-cyclopenten-1-yl) -2-butenal  (Example 2) in 70 ml of absolute ether within 45 minutes so zudo Siert that the reaction mixture was kept under gentle reflux.

Then allowed to react for 4 hours. After standing overnight, the mixture was poured into 1 liter of a saturated aqueous ammonium chloride solution. The organic phase was separated and the aqueous phase extracted with ether. The combined organic phases were dried over potassium carbonate and the residue obtained after concentration (70 g) was distilled over a small amount of soda on a 12 cm rotating band column under high vacuum. The main run was 52 g at 95 to 97 ° C and 0.03 mbar; GC purity was determined to be 93%. The IR spectrum (film on NaCl) showed bands at 3351 (-OH), 2957, 1374 and 1360 (according to dimethyl) as well as at 1114, 1090, 1072, 1056 and 1012 (CO) cm ^-1 .

Smell: intense creamy, fruity, woody, strong sandal note, milk note.

Example 5: 4-Ethyl-6- (2,2,3-trimethyl-3-cyclopenten-1-yl) -4-hexen-3-ol

In a dry 1 l three-necked flask, 11.2 g (0.46 mol) of magnesium turnings were covered with 100 ml of anhydrous ether under nitrogen, and 49.7 g (0.46 mol) of ethyl bromide were metered in slowly over the course of 40 minutes with stirring. To the resulting solution of Grignard reagent was then added 72 g of 2-ethyl-4- (2,2,3-trimethyl-3-cyclopenten-1-yl) -2-buten-1-al (Example 2) within 90 minutes Minutes dropped. After complete addition of the aldehyde was stirred for a further 5 hours at reflux temperature. The reaction mixture was then stirred into 1 L of a saturated aqueous ammonium chloride solution and the organic phase separated. The water phase was extracted with ether, the combined organic phases dried over potassium carbonate. After removal of the solvent left a residue of 65 g, which was distilled through a 12 cm Vigreux column. Yield: 37 g; Purity: 88% (according to GC). The further fractionation via a rotating band column gave 20.3 g of product having a boiling point of 100 to 102 ° C at 0.1 mbar and a gas chromatographically determined purity of 94%. The IR spectrum (film on NaCl) showed the following bands: 3361 (-OH), 2957, 1379 and 1359 (according to dimethyl) and 1011 (CO) and 799 (isolated C = C) cm ^-1 .

Odor: strong sandal scent, fruit note.  

Example 6: 2,4-Dimethyl-6- (2,2,3-trimethyl-3-cyclopenten-1-yl) -4-hexene 3-ol

In a dry 1 l three-necked flask, 11.2 g (0.46 mol) of magnesium shavings were covered with 100 ml of absolute ether and added dropwise with stirring 56.6 g (0.46 mol) of isopropyl bromide within 30 minutes so that the reaction mixture under was held at a gentle reflux. To the thus prepared Grignard reagent was added 67.2 g (0.35 mol) of 2-methyl-4- (2,2,3-trimethyl-3-cyclopenten-1-yl) -2-butene-1 -al, prepared according to Example IV, 1 of US Pat. No. 4,052,341, metered in with stirring within 45 minutes. After the addition of the aldehyde was stirred for 5 hours at reflux temperature and ste hen overnight at room temperature ste. Then, the reaction mixture was poured into 500 ml of a saturated aqueous ammonium chloride solution and extracted 3 times with 100 ml portions of ether. The organic phases were washed with water and dried over potassium carbonate. After filtration and concentration remained 48.3 g of residue, which were distilled on a 12 cm Vigreux column in a high vacuum de. The main run of 36 g went over at 113 to 118 ° C and 0.09 mbar and was not further purified. The IR spectrum (film on NaCl) showed bands at 3397 (-OH), 2953, 1382 and 1359 (according to dimethyl) as well as at 1012 (C-0) and 798 (isol C = C) cm ^-1 .

Smell: woody, fresh, sandal-note, balsamic.

3. Preparation of the comparative example Comparative Example 1: 3-Methyl-5- (2,2,3-trimethyl-3-cyclopenten-1-yl) - pentan-2-ol

3-Methyl-5- (2,2,3-trimethyl-3-cyclopenten-1-yl) -pentan-2-ol was prepared according to the Details of US Patent US 40 52 341 produced.  

4. Determination of the odor threshold values

The odor intensity of the compounds of the invention was in Ver equal to 3-methyl-5- (2,2,3-trimethyl-3-cyclopenten-1-yl) -pentan-2-ol be Right. For this purpose, solutions of the fragrances to be investigated in Prepared dipropylene glycol and each diluted so far, until just a smell could be perceived; in this way from a panel Of 16 subjects, certain minimal concentration for the Perception of the smell of the respective fragrance is called smell threshold value. For reasons of better comparability was the determined for Comparative Example 1 concentration for the Odor threshold value referred to as 1.0 and the values of Inventive Examples 3 to 6 based thereon.

It was found that the compounds of Examples 3 to 6 clearly ge had lower odor thresholds than the comparative example, See Table 1. For example, a value of 0.05 means for Examples 3 and 4 that the typical sandal odor already at 20 times higher dilution could be perceived as that of the comparative example.

Relative odor thresholds used compound, prepared according to rel. Odor threshold Example 3 0.05 Example 4 0.05 Example 5 0.50 Example 6 0.14 Comparative Example 1 1.00

5. Composition example

Flowery fantasy composition 7-hydroxy-6,7-dihydrocitronellal 120 parts α-Methyl 90 parts benzyl 90 parts Bergamot oil 90 parts Boisambrene forte (Henkel) 80 parts Citronellol 60 parts Floramat (Henkel) 60 parts Undecanal 10% in DPG 40 parts Rosacetate (Haarmann & Reimer) 40 parts linalool 30 parts Ylang-ylang 30 parts cinnamic alcohol 30 parts Styrax 50% in DPG 30 parts Ethylene brassylate (Haarmann & Reimer) 30 parts Benzoin resin 10% in DPG 30 parts Sedamon (Henkel) 20 parts α-amylcinnamaldehyde 20 parts Dodecanol 10% in DPG 20 parts Iris oil absolutely 10% in DPG 20 parts Rose oil absolutely 15 parts Jasmine oil absolutely 15 parts eugenol  5 parts 965 parts

The addition of 35 parts of 4-methyl-6- (2,2,3-trimethyl-3-cyclopenten-1-yl) - 4-hexen-3-ol, prepared according to Example 3, was added to the mixture Composition a natural woody note with balsamic and animalistic  Accents that rounded off the overall composition and the blu strengthened character. A similar effect was due to the addition of 35 parts of commercially available Sandel body or 35 parts of East Indian San can not reach the oilwood.

Claims (9)

1. Butenol derivatives of the general formula (I) wherein the radical R ^{1 is} hydrogen or an alkyl group having 1 to 4 C atoms and the radical R ^{2 is} an alkyl group having 1 to 4 C atoms, wherein R ^{2 is} the meaning of a methyl group except in the case where R ^{1 is} a methyl group. 2. butenol derivatives according to claim 1, wherein the radical R ^{1 is} hydrogen, Me ethyl or ethyl and the radical R ^{2 is} methyl or ethyl. 3. 4-Methyl-6- (2,2,3-trimethyl-3-cyclopenten-1-yl) -4-hexen-3-ol. 4. 4-Ethyl-6- (2,2,3-trimethyl-3-cyclopenten-1-yl) -4-hexen-3-ol. 5. 2,4-Dimethyl-6- (2,2,3-trimethyl-3-cyclopenten-1-yl) -4-hexen-3-ol. 6. Process for the preparation of butenol derivatives of the general formula (I) wherein the radical R ^{1 is} hydrogen or an alkyl group having 1 to 4 carbon atoms and the radical R 2 is an alkyl group having 1 to 4 carbon atoms, wherein R ² is excluded the meaning of a methyl group, if R ^{1 is} a methyl group, by Condensation of α-campholenaldehyde with the corresponding aldehydes or ketones to the corresponding unsaturated carbonyl compounds and subsequent reduction of the carbonyl function of these compounds z. B. with complex hydrides for OH function. 7. Use of the butenol derivatives according to one of claims 1 to 5 as Fragrances. 8. fragrance compositions containing one or more butene nol derivatives of the formula (I) according to claims 1 to 5 in an amount of 1 - 70 wt .-%, based on the entire composition. 9. Use of one or more butenol derivatives of the formula (I) according to claim 1 to 5 as fragrances in cosmetic preparations, technical products or alcoholic perfumery.