2,6,10-Trimethyl-10-hydroxy-dodeca-2,6,11-trien-al as a perfuming agent
United States Patent 3915901
A perfuming or odour-modifying agent consisting essentially of or comprising 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al. A process for the manufacture of 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al.
Application Number:
05/483553
Publication Date:
10/28/1975
Filing Date:
06/27/1974
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Export Citation:
Assignee:
Firmenich S.A. (Geneva, CH)
Primary Class:
Other Classes:
568/461, 568/486, 568/496
International Classes:
C07C45/59; C07C45/72; C07C47/263; C11B9/00; C07C45/00; C07C47/20; C11B9/00
Field of Search:
252/522
Primary Examiner:
O'keefe, Veronica
Attorney, Agent or Firm:
Pennie & Edmonds
Claims:
I claim
1. A process for improving, enhancing or otherwise modifying the odoriferous properties of perfumes, perfumed products and natural or synthetic essential oils which comprises adding thereto an odour-modifying amount of 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al.
2. An odoriferous composition selected from the class consisting of perfumes, perfumed products and natural or artificial essential oils having added thereto an odour-modifying amount of 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al.
3. A perfume composition which comprises as one of its odoriferous ingredients 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al.
4. A perfume composition which comprises 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al and a diluent or a carrier.
1. A process for improving, enhancing or otherwise modifying the odoriferous properties of perfumes, perfumed products and natural or synthetic essential oils which comprises adding thereto an odour-modifying amount of 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al.
2. An odoriferous composition selected from the class consisting of perfumes, perfumed products and natural or artificial essential oils having added thereto an odour-modifying amount of 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al.
3. A perfume composition which comprises as one of its odoriferous ingredients 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al.
4. A perfume composition which comprises 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al and a diluent or a carrier.
Description:
BACKGROUND OF THE INVENTION
The invention relates to the art of perfumery, more particularly to a perfuming or odour-modifying agent, and to compositions and products comprising the said agent.
2,6,10-Trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al, also called hydroxysinensal, having the following structural formula ##EQU1## is a known compound (cf. West German patent application DOS 2,143,992 laid open to public inspection) which is used as an intermediate in the synthesis of α-sinensal and β-sinensal, the latter being natural constituents of the mandarin and tangerine flavour.
The structure of hydroxysinensal being very similar to that of α- and β-sinensal, it was reasonable to expect that hydroxysinensal would also have a similar odour, i.e., would develop a mandarin- or tangerine-like odour or at least an odour reminiscent of mandarin or tangerine, as it is suggested in the above-mentioned West German patent application. However, I could not confirm this. To my surprise I found that the odour of hydroxysinensal is quite different from that of the sinensals. Its odour is not fruity but floral and reminiscent of the fragrance developed by the lily of the valley and is very tenacious. Furthermore, the odour of aldehyde I is free from the citrus note which characterizes the sinensals. Hydroxysinensal as such already constitutes a complete perfume. It can be used as a base in the preparation of perfumes or as a modifier to be added to perfume compositions and permits to obtain very interesting floral olfactive effects.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a process for improving, enhancing or otherwise modifying the odoriferous properties of perfume compositions, perfumed products and natural or synthetic essential oils by using 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al as an odoriferous ingredient or additive.
Another object of the invention is to provide odoriferous compositions, such as perfumes, perfumed products and essential oils, having added thereto an odour-modifying amount of 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al.
The term "perfumed products" includes e.g. soaps, cosmetic products, detergents and the like.
DETAILED DESCRIPTION
Hydroxysinensal can be used alone, i.e., without being admixed to other odoriferous substances, as a fragrance. Preferably, it is used in diluted form. The diluents or solvents usually used in perfumery, e.g. ethyl alcohol or diethyl phthalate, can be used for this purpose. Hydroxysinensal as such can be used for perfuming soaps, cosmetic products, detergents and the like.
When hydroxysinensal is used as perfume ingredient together with other odoriferous substances in perfume compositions, its concentration can vary within wide limits, e.g. between 2 and 20 % based on the total weight of a perfume composition. However, the concentration of hydroxysinensal can exceed 20 % and reach for example 50 % or more when special olfactive effects are to be obtained. As a rule, hydroxysinensal imparts strong floral odour notes to perfume compositions and enhances as well as harmonizes the floral odour component of the perfumes to which it is added.
According to the invention 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al is prepared by reacting nerolidol (II) with N-bromosuccinimide in order to obtain 2-methyl-2-vinyl-5-(1,5-dimethyl-1-bromo-hex-4-en-1-yl)-tetr ahydrofuran (III), converting the latter to its mono-ozonide and reducing the ozonide in order to obtain 2-methyl-2-vinyl-5-(1-methyl-1-bromo-3-formyl-prop-1-yl)-tet rahydrofuran (IV), acetalizing the latter, reacting the resulting acetal (V) with a reducing metal in a substantially anhydrous medium and subsequently with water, hydrolysing the resulting acetal of 4,8-dimethyl-8-hydroxy-deca-4,9-dien-1-al (VI) in order to obtain 4,8-dimethyl-8-hydroxy-deca-4,9-dien-1-al (VII), and subjecting the latter to a Wittig reaction with 1-formyl-ethylidenetriphenyl-phosphorane in order to obtain 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al (I).
The above-defined process can be illustrated as follows: ##EQU2## R = alkyl group or 2R = alkylene group
As a starting compound (+)- or (-)-nerolidol can be used in the form of its cis- or trans-isomer or of mixtures of these isomers.
The reaction between nerolidol and N-bromosuccinimide is conveniently carried out at temperatures neighbouring 20°C, preferably at 18°-20°C. The reaction time can vary between about 27 and 170 hours. As to the other reaction conditions, the method described in Helv. Chim. Acta 54, 461 (1971) can be applied.
The ozonolysis of compound III can be carried out by known methods, e.g. at -70°C in methanol. As a reducing agent for the reduction of the ozonide e.g. methyl sulphide, triphenylphosphine or trimethylphosphite can be used.
The acetalisation of aldehyde VI can be carried out by usual methods. The acetal can be either cyclic of non-cyclic.
The dehydrobromination of acetal V can be carried out by means of metallic sodium in a substantially anhydrous medium, e.g. in tetrahydrofuran, or by means of zinc powder in acetic acid.
The Wittig reagent with which aldehyde VII is reacted can be obtained by the method described in Helv. Chim. Acta 50, 2445 (1967).
2,6,10-Trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al can theoretically exist in the form of four configuration isomers, viz. the 2cis,6cis, 2cis,6trans, 2trans,6trans and 2trans,6cis isomers. The isomers having cis-configuration in position 2 are, however, not stable. In the process of the invention mixtures of the 2trans,6trans and 2trans,6cis isomers are formed as a rule. The ratio in which the two isomers are formed varies within certain limits and can, e.g., be about 30 % of the 2trans,6cis isomer to 70 % of the 2trans,6trans isomer. Since the two isomers have similar olfactive properties, it is not necessary to separate them before they are used as perfuming agents. The mixture of isomers as obtained by the process of the invention can be used directly for perfuming purposes.
It is obvious that instead of 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al its precursors, e.g. its acetals which will yield the aldehyde under acid conditions, can also be used.
The invention is further illustrated by the following Examples wherein temperatures are given in degrees centigrade.
EXAMPLE 1
A perfume base was prepared by mixing the following ingredients: Ingredients Parts by weight ______________________________________ 1,1-Dimethyl-4-acetyl-6- tert.-butyl-indan 10 Neroli bigarade 10 Undecenal 10%* 40 Nonadienal 1%* 20 Isobutyl salicylate 40 Citronellol 100 Linalool 100 iso-Methyl-α-ionone 100 Phenylethylalcohol 100 Ylang 60 Oriental santal 40 Benzyl acetate 100 Linalyl acetate 100 Methyl dihydrojasmonate 10%* 80 Diethyl phthalate 100 Total 1000 ______________________________________ *in diethyl phthalate
This perfume base developed an unspecific floral odour. By adding 100 parts by weight of hydroxysinensal to 900 parts of the perfume base a perfume composition developing a strong lily of the valley-like odour was obtained. This perfume was particularly suitable for perfuming facial creams.
For the purpose of comparison, 10 parts by weight of α-sinensal were added to 990 parts of the same perfume base. The resulting composition developed an odour which was characterized by a strong citrus note. The lily of the valley-like odour had completely disappeared.
EXAMPLE 2
A perfume base was prepared by mixing the following ingredients: 8n
Ingredients Parts by weight ______________________________________ Nonanal 10%* 10 Undecenal 10%* 30 Dodecanal 10 Decanal 20 Methylnonylacetic aldehyde 10%* 30 Synthetic bergamot 90 Oriental santal 10 Phenylmethylcarbinyl acetate 20 Tarragon 10%* 30 Synthetic ambergris 10%* 50 Synthetic civet 10%* 20 Synthetic jasmin 70 Cumarin 30 Musk ketone 30 Ambrette musk 20 Cyclopentadecanolide 10%* 20 Deterpenated orange oil 20 Vetyveryl acetate 50 Vetyverol 50 Heliotropin 40 Isoeugenol 30 Hexylcinnamic aldehyde 40 Synthetic Bulgarian rose oil 100 Synthetic rose absolute 20 Ylang 80 iso-Methyl-α-ionone 70 Vanillin 10%* 10 Total 1000 ______________________________________ *in diethyl phthalate
This perfume base developed a warm and somewhat amber-like odour. 100 parts by weight of hydroxysinensal were added to the perfume base. The resulting perfume composition developed a substantially improved and enhanced fragrance. Whereas in the perfume base the floral notes were somewhat overshadowed by the amber note, the floral notes fully developed from the perfume composition containing hydroxysinensal. Furthermore, this perfume developed a particularly elegant fragrance.
Hydroxysinensal which has a discrete but very tenacious floral note enhances and harmonizes the floral notes in perfumes and is, therefore, a very valuable perfume ingredient.
When the same amount, or even only 1 %, of α-sinensal is added to the perfume base instead of hydroxysinensal, the olfactive properties of the perfume base are totally changed. A strong fruity odour overshadows entirely all the other odour notes of the perfume base.
EXAMPLE 3
A mixture of 44.4 g (0.2 mole) of (±)-nerolidol (II, mixture of cis and trans isomers), 37.4 g (0.21 mole) of N-bromosuccinimide and 500 ml of CCL 4 was stirred for 6 days at 18°-20°. One volume of petroleum ether (boiling range 30°-50°) was added to the reaction mixture, and the precipitated solid was filtered off. 0.5 g of sodium acetate was added to the filtrate which was then concentrated at 10 mm Hg. There were thus obtained 63 g of 2-methyl-2-vinyl-5-(1,5-dimethyl-1-bromo-hex-4-en-l-yl)-tetr ahydrofuran (II) as a residue. This residue was taken up in 630 ml of methanol, and the solution was treated at -70° with a stream of ozone-containing oxygen for 31/2 hours (corresponding to 0.2 mole of 0 3 ). The solution was maintained at -70° and treated with a vigorous stream of nitrogen, and 30 ml of methyl sulphide were added. The reaction mixture was allowed to warm up to 20° within 12 hours under nitrogen. The reaction mixture was concentrated at 10 mm Hg. The residue was taken up in ether (two separating funnels). The ether solution was washed three times with water and then with brine, subsequently dried over magnesium sulphate and concentrated. A residue consisting of 2-methyl-2-vinyl-5-(1-methyl-1-bromo-3-formyl-prop-1-yl)-tet rahydrofuran (III) was obtained.
The residue was refluxed in a mixture of 250 ml of benzene, 16.1 g (0.26 mole) of ethyleneglycol and 100 mg of p-toluenesulphonic acid (using a Dean-Stark separator). The heating was continued for 2 hours after the formation of water had stopped. Then, 100 ml of benzene were slowly removed by distillation. The remaining solution was washed with 10 % sodium carbonate solution (3 times) and with brine (twice). After removal of the solvent at 10 mm Hg the ethylene acetal V of aldehyde IV was obtained as a residue.
The residue was taken up in 150 ml of anhydrous tetrahydrofuran, and the resulting solution was added to a stirred suspension of 9.65 g (0.42 mole) of powdered soda in 500 ml of the same solvent. After stirring for a few hours at 20°, the temperature of the reaction mixture spontaneously rose. The reaction mixture was maintained at 40°for 6 hours (first by cooling and then by heating). A further quantity of 4.8 g (0.2 mole) of powdered sodium suspended in 100 ml of tetrahydrofuran was added, and the reaction mixture was stirred for 15 hours at 40°. After cooling the liquid phase was carefully separated from the agglomerated sodium. A small quantity of ethanol was added to the liquid phase, and then the solvent was removed under reduced pressure. The residue was taken up in water. The resulting solution was extracted with ether (twice). The ether extract was washed with water (5 times) and then rapidly distilled at 0.001 mm Hg. The distillate was again fractionated in a Vigreux column (30 cm; equipped with an adjustable reflux head). 21.4 g (44.6 % based on nerolidol) of the ethylene acetal of 4,8-dimethyl-8-hydroxy-deca-4,9-dien-1-al (VI), b.p. 97°-105°/0.001 mm Hg, were thus isolated. This product consisted of a mixture of the cis and trans isomers which were separated by distillation in a spinning band column. The cis isomer is more volatile than the trans isomer.
Acetal VI cis: d 4 20 = 0.9977; n D 20 = 1.4816;
Ir (film): 920, 990, 1410, 1640, 3100 (--CH=CH 2 ), 1140 (C--O), 3470 cm - 1 (OH);
Ms: m + almost invisible at m/e 240, base peak at m/e 73;
Nmr: δ= 1.25 (3h, s), 1.69 (3H, s broad), 1.30-2.30 (9H, m), 3.87 (4H, m), 4.80 (1H, t, J = 4.5 cps), 4.88-5.35 (3H, m), 5.92 (1H, d/d, J = 17, J' = 10 cps) ppm.
Calculated for C 14 H 24 O 3 : C--69.96, H--10.07 %. Found: C--69.95, H--10.21 %.
Acetal VI trans: d 4 20 = 0.9975; n D 20 = 1.4833;
Ir (film): 920, 1410, 1640, 3100 (--CH=CH 2 ), 1140 (C--O), 3470 cm - 1 (OH);
Ms: m + almost invisible at m/e 240, base peak at m/e 86;
Nmr: δ = 1.25 (3h, s), 1.62 (3H, s broad), 1.30-2.30 (9H, m), 3.85 (4H, m), 4.80 (1H, t, J = 4.5 cps), 4.88-5.35 (3H, m), 5.92 (1H, d/d, J = 17, J ' = 10 cps) ppm.
A solution of 4.85 g (20 mmoles) of one of the acetals VI in a mixture of 120 ml dioxan and 45 ml of 0.02 N sulphuric acid was refluxed for 3 hours. The solution was allowed to cool to 20°, and 10 ml of 5 % aqueous sodium bicarbonate were added thereto. The reaction mixture was stirred for 15 minutes. After removal of the dioxan the residue was taken up in ether. The solution was washed with 5 % aqueous sodium bicarbonate (once), water (three times) and brine (once). After the usual treatment and distillation 2.84 g (72 %) of a mixture of cis and trans 4,8-dimethyl-8-hydroxy-deca-4,9-dien-1-als were obtained.
Aldehyde VII cis: b.p. 83°-85°/0.001 Torr; d 4 20 = 0.9661; n D 20 = 1.4828;
Ir (film): 915, 990, 1410, 1635, 3080 (--CH=CH 2 ), 1105 (C--O), 1715 (C=0), 2720, 2850 (--CHO), 3450 cm - 1 (OH);
Ms: m + invisible, M-18 at m/e 178, base peak at m/e 71;
Nmr: δ = 1.23 (3h, s), 1.66 (3H, s broad), 2.37 (3H, m narrow), 1.30-2.50 (5H, m), 2.60 (1H, s, OH), 4.80-5.30 (3H, m), 5.88 (1H, d/d, J = 17, J' = 10 cps), 9.71 (1H, t, J = about 1.5 cps) ppm.
Aldehyde VII trans: b.p. 93°-95°/0.001 Torr; d 4 20 = 0.9700; n D 20 = 1.4800;
Ir (film): 915; 990, 1410, 1635, 3080 (--CH=CH 2 ), 1110 (C--O), 1715 (C=O), 2720, 2850 (--CHO), 3450 cm - 1 (OH);
Ms: m + invisible, M-18 at m/e 178, base peak at m/e 71;
Nmr: δ = 1.26 (3h, s), 1.60 (3H, s broad), 1.30-2.60 (9H, m), 4.80-5.30 (3H, m), 5.83 (1H, d/d, J = 17, J' = 10 cps), 9.32 (1H, t, J = about 1.5 cps) ppm.
Calculated for C 12 H 20 O 2 : C--73.43, H--10.27 %. Found: C--73.40, H--10.41 %.
A mixture of 1.147 g (5.83 mmoles) of cis aldehyde VII, 1.95 g (6.14 mmoles) of 1-formyl-ethylidene-triphenylphosphorane and 12 ml of anhydrous benzene was refluxed for 50 hours in a nitrogen atmosphere. The solvent was removed at reduced pressure, and the residue was taken up in a 1:1 mixture of ether and petroleum ether (boiling range 30°-50°). After filtration of the solution the filtrate was concentrated. The residue was distilled at 0.001 mm Hg, b.p. 112°. 1.069 g (77.4 %) of 2,6,10-trimethyl-10-hydroxy-dodeca-2trans,6cis,10-trien-1-al (I) were obtained. This product had the following physical properties:
d 4 20 = 0.9577; n D 20 = 1.5009;
Ir (film): 915, 990, 1400, 3080 (--CH=CH 2 ), 1100 (C--O), 1635, ##EQU3## 2700, 2850 (--CHO), 3450 cm - 1 (OH); MS: M + invisible, M-18 at m/e 218, intense fragments at m/e 43 (base peak), 55, 71, 93;
Nmr: δ = 1.26 (3h, s), 1.70 (6H, s broad), 2.62 (1H, s, OH), 1.30-2.80 (8H, m), 4.80-5.40 (3H, m), 5.86 (1H, d/d, J = 17, J' = 10 cps), 6.43 (1H, t, J = 6 cps), 10.33 (1H, s) ppm.
This latter signal (proton of --CHO) appeared at δ = 9.27 when the measurement was made in CCl 4 .
3.65 g (16.5 mmoles) of trans aldehyde VII were reacted in the manner described above with 5.53 g (17.4 mmoles) of 1-formyl-ethylidene-triphenyl-phosphorane in 35 ml of anhydrous benzene. 3.6 g of a crude product boiling at 115°-122°/0.001 mm Hg were obtained. This product was purified by chromatography on a column of 100 g of silicagel (Mallinckrodt, 100 mesh). Elution with a 7:3 mixture of benzene and ether yielded 2.632 g (67.5 %) of 2,6,10-trimethyl-10-hydroxy-dodeca-2trans,6trans,11-trien-1- al. This compound had the following physical properties:
B.p. 118- 120°/0.001 mm Hg; d 4 20 = 0.9557; n D 20 = 1.5009;
Ir (film): 915, 990, 1400, 3080 (--CH=CH 2 ), 1635, ##EQU4## 2700, 2850 (--CHO), 3450 cm - 1 (OH); MS: M + invisible, M-18 at m/e 218, intense fragments at m/e 43 (base peak), 55, 93;
Nmr: δ = 1.25 (3h, s), 1.62 (3H, s broad), 1.71 (3H, s broad), 1.30-2.70 (8H, m), 2.50 (1H, s, OH), 4.86-5.33 (3H, m), 5.91 (1H, d/d, J = 17, J' = 10 cps), 6.45 (1H, t, J = 6 cps), 9.60 (1H, s) ppm.
This latter signal (proton of --CHO) appeared at δ = 9.27 when the measurement was made in CCl 4 .
The invention relates to the art of perfumery, more particularly to a perfuming or odour-modifying agent, and to compositions and products comprising the said agent.
2,6,10-Trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al, also called hydroxysinensal, having the following structural formula ##EQU1## is a known compound (cf. West German patent application DOS 2,143,992 laid open to public inspection) which is used as an intermediate in the synthesis of α-sinensal and β-sinensal, the latter being natural constituents of the mandarin and tangerine flavour.
The structure of hydroxysinensal being very similar to that of α- and β-sinensal, it was reasonable to expect that hydroxysinensal would also have a similar odour, i.e., would develop a mandarin- or tangerine-like odour or at least an odour reminiscent of mandarin or tangerine, as it is suggested in the above-mentioned West German patent application. However, I could not confirm this. To my surprise I found that the odour of hydroxysinensal is quite different from that of the sinensals. Its odour is not fruity but floral and reminiscent of the fragrance developed by the lily of the valley and is very tenacious. Furthermore, the odour of aldehyde I is free from the citrus note which characterizes the sinensals. Hydroxysinensal as such already constitutes a complete perfume. It can be used as a base in the preparation of perfumes or as a modifier to be added to perfume compositions and permits to obtain very interesting floral olfactive effects.
SUMMARY OF THE INVENTION
It is an object of the invention to provide a process for improving, enhancing or otherwise modifying the odoriferous properties of perfume compositions, perfumed products and natural or synthetic essential oils by using 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al as an odoriferous ingredient or additive.
Another object of the invention is to provide odoriferous compositions, such as perfumes, perfumed products and essential oils, having added thereto an odour-modifying amount of 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al.
The term "perfumed products" includes e.g. soaps, cosmetic products, detergents and the like.
DETAILED DESCRIPTION
Hydroxysinensal can be used alone, i.e., without being admixed to other odoriferous substances, as a fragrance. Preferably, it is used in diluted form. The diluents or solvents usually used in perfumery, e.g. ethyl alcohol or diethyl phthalate, can be used for this purpose. Hydroxysinensal as such can be used for perfuming soaps, cosmetic products, detergents and the like.
When hydroxysinensal is used as perfume ingredient together with other odoriferous substances in perfume compositions, its concentration can vary within wide limits, e.g. between 2 and 20 % based on the total weight of a perfume composition. However, the concentration of hydroxysinensal can exceed 20 % and reach for example 50 % or more when special olfactive effects are to be obtained. As a rule, hydroxysinensal imparts strong floral odour notes to perfume compositions and enhances as well as harmonizes the floral odour component of the perfumes to which it is added.
According to the invention 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al is prepared by reacting nerolidol (II) with N-bromosuccinimide in order to obtain 2-methyl-2-vinyl-5-(1,5-dimethyl-1-bromo-hex-4-en-1-yl)-tetr ahydrofuran (III), converting the latter to its mono-ozonide and reducing the ozonide in order to obtain 2-methyl-2-vinyl-5-(1-methyl-1-bromo-3-formyl-prop-1-yl)-tet rahydrofuran (IV), acetalizing the latter, reacting the resulting acetal (V) with a reducing metal in a substantially anhydrous medium and subsequently with water, hydrolysing the resulting acetal of 4,8-dimethyl-8-hydroxy-deca-4,9-dien-1-al (VI) in order to obtain 4,8-dimethyl-8-hydroxy-deca-4,9-dien-1-al (VII), and subjecting the latter to a Wittig reaction with 1-formyl-ethylidenetriphenyl-phosphorane in order to obtain 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al (I).
The above-defined process can be illustrated as follows: ##EQU2## R = alkyl group or 2R = alkylene group
As a starting compound (+)- or (-)-nerolidol can be used in the form of its cis- or trans-isomer or of mixtures of these isomers.
The reaction between nerolidol and N-bromosuccinimide is conveniently carried out at temperatures neighbouring 20°C, preferably at 18°-20°C. The reaction time can vary between about 27 and 170 hours. As to the other reaction conditions, the method described in Helv. Chim. Acta 54, 461 (1971) can be applied.
The ozonolysis of compound III can be carried out by known methods, e.g. at -70°C in methanol. As a reducing agent for the reduction of the ozonide e.g. methyl sulphide, triphenylphosphine or trimethylphosphite can be used.
The acetalisation of aldehyde VI can be carried out by usual methods. The acetal can be either cyclic of non-cyclic.
The dehydrobromination of acetal V can be carried out by means of metallic sodium in a substantially anhydrous medium, e.g. in tetrahydrofuran, or by means of zinc powder in acetic acid.
The Wittig reagent with which aldehyde VII is reacted can be obtained by the method described in Helv. Chim. Acta 50, 2445 (1967).
2,6,10-Trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al can theoretically exist in the form of four configuration isomers, viz. the 2cis,6cis, 2cis,6trans, 2trans,6trans and 2trans,6cis isomers. The isomers having cis-configuration in position 2 are, however, not stable. In the process of the invention mixtures of the 2trans,6trans and 2trans,6cis isomers are formed as a rule. The ratio in which the two isomers are formed varies within certain limits and can, e.g., be about 30 % of the 2trans,6cis isomer to 70 % of the 2trans,6trans isomer. Since the two isomers have similar olfactive properties, it is not necessary to separate them before they are used as perfuming agents. The mixture of isomers as obtained by the process of the invention can be used directly for perfuming purposes.
It is obvious that instead of 2,6,10-trimethyl-10-hydroxy-dodeca-2,6,11-trien-1-al its precursors, e.g. its acetals which will yield the aldehyde under acid conditions, can also be used.
The invention is further illustrated by the following Examples wherein temperatures are given in degrees centigrade.
EXAMPLE 1
A perfume base was prepared by mixing the following ingredients: Ingredients Parts by weight ______________________________________ 1,1-Dimethyl-4-acetyl-6- tert.-butyl-indan 10 Neroli bigarade 10 Undecenal 10%* 40 Nonadienal 1%* 20 Isobutyl salicylate 40 Citronellol 100 Linalool 100 iso-Methyl-α-ionone 100 Phenylethylalcohol 100 Ylang 60 Oriental santal 40 Benzyl acetate 100 Linalyl acetate 100 Methyl dihydrojasmonate 10%* 80 Diethyl phthalate 100 Total 1000 ______________________________________ *in diethyl phthalate
This perfume base developed an unspecific floral odour. By adding 100 parts by weight of hydroxysinensal to 900 parts of the perfume base a perfume composition developing a strong lily of the valley-like odour was obtained. This perfume was particularly suitable for perfuming facial creams.
For the purpose of comparison, 10 parts by weight of α-sinensal were added to 990 parts of the same perfume base. The resulting composition developed an odour which was characterized by a strong citrus note. The lily of the valley-like odour had completely disappeared.
EXAMPLE 2
A perfume base was prepared by mixing the following ingredients: 8n
Ingredients Parts by weight ______________________________________ Nonanal 10%* 10 Undecenal 10%* 30 Dodecanal 10 Decanal 20 Methylnonylacetic aldehyde 10%* 30 Synthetic bergamot 90 Oriental santal 10 Phenylmethylcarbinyl acetate 20 Tarragon 10%* 30 Synthetic ambergris 10%* 50 Synthetic civet 10%* 20 Synthetic jasmin 70 Cumarin 30 Musk ketone 30 Ambrette musk 20 Cyclopentadecanolide 10%* 20 Deterpenated orange oil 20 Vetyveryl acetate 50 Vetyverol 50 Heliotropin 40 Isoeugenol 30 Hexylcinnamic aldehyde 40 Synthetic Bulgarian rose oil 100 Synthetic rose absolute 20 Ylang 80 iso-Methyl-α-ionone 70 Vanillin 10%* 10 Total 1000 ______________________________________ *in diethyl phthalate
This perfume base developed a warm and somewhat amber-like odour. 100 parts by weight of hydroxysinensal were added to the perfume base. The resulting perfume composition developed a substantially improved and enhanced fragrance. Whereas in the perfume base the floral notes were somewhat overshadowed by the amber note, the floral notes fully developed from the perfume composition containing hydroxysinensal. Furthermore, this perfume developed a particularly elegant fragrance.
Hydroxysinensal which has a discrete but very tenacious floral note enhances and harmonizes the floral notes in perfumes and is, therefore, a very valuable perfume ingredient.
When the same amount, or even only 1 %, of α-sinensal is added to the perfume base instead of hydroxysinensal, the olfactive properties of the perfume base are totally changed. A strong fruity odour overshadows entirely all the other odour notes of the perfume base.
EXAMPLE 3
A mixture of 44.4 g (0.2 mole) of (±)-nerolidol (II, mixture of cis and trans isomers), 37.4 g (0.21 mole) of N-bromosuccinimide and 500 ml of CCL 4 was stirred for 6 days at 18°-20°. One volume of petroleum ether (boiling range 30°-50°) was added to the reaction mixture, and the precipitated solid was filtered off. 0.5 g of sodium acetate was added to the filtrate which was then concentrated at 10 mm Hg. There were thus obtained 63 g of 2-methyl-2-vinyl-5-(1,5-dimethyl-1-bromo-hex-4-en-l-yl)-tetr ahydrofuran (II) as a residue. This residue was taken up in 630 ml of methanol, and the solution was treated at -70° with a stream of ozone-containing oxygen for 31/2 hours (corresponding to 0.2 mole of 0 3 ). The solution was maintained at -70° and treated with a vigorous stream of nitrogen, and 30 ml of methyl sulphide were added. The reaction mixture was allowed to warm up to 20° within 12 hours under nitrogen. The reaction mixture was concentrated at 10 mm Hg. The residue was taken up in ether (two separating funnels). The ether solution was washed three times with water and then with brine, subsequently dried over magnesium sulphate and concentrated. A residue consisting of 2-methyl-2-vinyl-5-(1-methyl-1-bromo-3-formyl-prop-1-yl)-tet rahydrofuran (III) was obtained.
The residue was refluxed in a mixture of 250 ml of benzene, 16.1 g (0.26 mole) of ethyleneglycol and 100 mg of p-toluenesulphonic acid (using a Dean-Stark separator). The heating was continued for 2 hours after the formation of water had stopped. Then, 100 ml of benzene were slowly removed by distillation. The remaining solution was washed with 10 % sodium carbonate solution (3 times) and with brine (twice). After removal of the solvent at 10 mm Hg the ethylene acetal V of aldehyde IV was obtained as a residue.
The residue was taken up in 150 ml of anhydrous tetrahydrofuran, and the resulting solution was added to a stirred suspension of 9.65 g (0.42 mole) of powdered soda in 500 ml of the same solvent. After stirring for a few hours at 20°, the temperature of the reaction mixture spontaneously rose. The reaction mixture was maintained at 40°for 6 hours (first by cooling and then by heating). A further quantity of 4.8 g (0.2 mole) of powdered sodium suspended in 100 ml of tetrahydrofuran was added, and the reaction mixture was stirred for 15 hours at 40°. After cooling the liquid phase was carefully separated from the agglomerated sodium. A small quantity of ethanol was added to the liquid phase, and then the solvent was removed under reduced pressure. The residue was taken up in water. The resulting solution was extracted with ether (twice). The ether extract was washed with water (5 times) and then rapidly distilled at 0.001 mm Hg. The distillate was again fractionated in a Vigreux column (30 cm; equipped with an adjustable reflux head). 21.4 g (44.6 % based on nerolidol) of the ethylene acetal of 4,8-dimethyl-8-hydroxy-deca-4,9-dien-1-al (VI), b.p. 97°-105°/0.001 mm Hg, were thus isolated. This product consisted of a mixture of the cis and trans isomers which were separated by distillation in a spinning band column. The cis isomer is more volatile than the trans isomer.
Acetal VI cis: d 4 20 = 0.9977; n D 20 = 1.4816;
Ir (film): 920, 990, 1410, 1640, 3100 (--CH=CH 2 ), 1140 (C--O), 3470 cm - 1 (OH);
Ms: m + almost invisible at m/e 240, base peak at m/e 73;
Nmr: δ= 1.25 (3h, s), 1.69 (3H, s broad), 1.30-2.30 (9H, m), 3.87 (4H, m), 4.80 (1H, t, J = 4.5 cps), 4.88-5.35 (3H, m), 5.92 (1H, d/d, J = 17, J' = 10 cps) ppm.
Calculated for C 14 H 24 O 3 : C--69.96, H--10.07 %. Found: C--69.95, H--10.21 %.
Acetal VI trans: d 4 20 = 0.9975; n D 20 = 1.4833;
Ir (film): 920, 1410, 1640, 3100 (--CH=CH 2 ), 1140 (C--O), 3470 cm - 1 (OH);
Ms: m + almost invisible at m/e 240, base peak at m/e 86;
Nmr: δ = 1.25 (3h, s), 1.62 (3H, s broad), 1.30-2.30 (9H, m), 3.85 (4H, m), 4.80 (1H, t, J = 4.5 cps), 4.88-5.35 (3H, m), 5.92 (1H, d/d, J = 17, J ' = 10 cps) ppm.
A solution of 4.85 g (20 mmoles) of one of the acetals VI in a mixture of 120 ml dioxan and 45 ml of 0.02 N sulphuric acid was refluxed for 3 hours. The solution was allowed to cool to 20°, and 10 ml of 5 % aqueous sodium bicarbonate were added thereto. The reaction mixture was stirred for 15 minutes. After removal of the dioxan the residue was taken up in ether. The solution was washed with 5 % aqueous sodium bicarbonate (once), water (three times) and brine (once). After the usual treatment and distillation 2.84 g (72 %) of a mixture of cis and trans 4,8-dimethyl-8-hydroxy-deca-4,9-dien-1-als were obtained.
Aldehyde VII cis: b.p. 83°-85°/0.001 Torr; d 4 20 = 0.9661; n D 20 = 1.4828;
Ir (film): 915, 990, 1410, 1635, 3080 (--CH=CH 2 ), 1105 (C--O), 1715 (C=0), 2720, 2850 (--CHO), 3450 cm - 1 (OH);
Ms: m + invisible, M-18 at m/e 178, base peak at m/e 71;
Nmr: δ = 1.23 (3h, s), 1.66 (3H, s broad), 2.37 (3H, m narrow), 1.30-2.50 (5H, m), 2.60 (1H, s, OH), 4.80-5.30 (3H, m), 5.88 (1H, d/d, J = 17, J' = 10 cps), 9.71 (1H, t, J = about 1.5 cps) ppm.
Aldehyde VII trans: b.p. 93°-95°/0.001 Torr; d 4 20 = 0.9700; n D 20 = 1.4800;
Ir (film): 915; 990, 1410, 1635, 3080 (--CH=CH 2 ), 1110 (C--O), 1715 (C=O), 2720, 2850 (--CHO), 3450 cm - 1 (OH);
Ms: m + invisible, M-18 at m/e 178, base peak at m/e 71;
Nmr: δ = 1.26 (3h, s), 1.60 (3H, s broad), 1.30-2.60 (9H, m), 4.80-5.30 (3H, m), 5.83 (1H, d/d, J = 17, J' = 10 cps), 9.32 (1H, t, J = about 1.5 cps) ppm.
Calculated for C 12 H 20 O 2 : C--73.43, H--10.27 %. Found: C--73.40, H--10.41 %.
A mixture of 1.147 g (5.83 mmoles) of cis aldehyde VII, 1.95 g (6.14 mmoles) of 1-formyl-ethylidene-triphenylphosphorane and 12 ml of anhydrous benzene was refluxed for 50 hours in a nitrogen atmosphere. The solvent was removed at reduced pressure, and the residue was taken up in a 1:1 mixture of ether and petroleum ether (boiling range 30°-50°). After filtration of the solution the filtrate was concentrated. The residue was distilled at 0.001 mm Hg, b.p. 112°. 1.069 g (77.4 %) of 2,6,10-trimethyl-10-hydroxy-dodeca-2trans,6cis,10-trien-1-al (I) were obtained. This product had the following physical properties:
d 4 20 = 0.9577; n D 20 = 1.5009;
Ir (film): 915, 990, 1400, 3080 (--CH=CH 2 ), 1100 (C--O), 1635, ##EQU3## 2700, 2850 (--CHO), 3450 cm - 1 (OH); MS: M + invisible, M-18 at m/e 218, intense fragments at m/e 43 (base peak), 55, 71, 93;
Nmr: δ = 1.26 (3h, s), 1.70 (6H, s broad), 2.62 (1H, s, OH), 1.30-2.80 (8H, m), 4.80-5.40 (3H, m), 5.86 (1H, d/d, J = 17, J' = 10 cps), 6.43 (1H, t, J = 6 cps), 10.33 (1H, s) ppm.
This latter signal (proton of --CHO) appeared at δ = 9.27 when the measurement was made in CCl 4 .
3.65 g (16.5 mmoles) of trans aldehyde VII were reacted in the manner described above with 5.53 g (17.4 mmoles) of 1-formyl-ethylidene-triphenyl-phosphorane in 35 ml of anhydrous benzene. 3.6 g of a crude product boiling at 115°-122°/0.001 mm Hg were obtained. This product was purified by chromatography on a column of 100 g of silicagel (Mallinckrodt, 100 mesh). Elution with a 7:3 mixture of benzene and ether yielded 2.632 g (67.5 %) of 2,6,10-trimethyl-10-hydroxy-dodeca-2trans,6trans,11-trien-1- al. This compound had the following physical properties:
B.p. 118- 120°/0.001 mm Hg; d 4 20 = 0.9557; n D 20 = 1.5009;
Ir (film): 915, 990, 1400, 3080 (--CH=CH 2 ), 1635, ##EQU4## 2700, 2850 (--CHO), 3450 cm - 1 (OH); MS: M + invisible, M-18 at m/e 218, intense fragments at m/e 43 (base peak), 55, 93;
Nmr: δ = 1.25 (3h, s), 1.62 (3H, s broad), 1.71 (3H, s broad), 1.30-2.70 (8H, m), 2.50 (1H, s, OH), 4.86-5.33 (3H, m), 5.91 (1H, d/d, J = 17, J' = 10 cps), 6.45 (1H, t, J = 6 cps), 9.60 (1H, s) ppm.
This latter signal (proton of --CHO) appeared at δ = 9.27 when the measurement was made in CCl 4 .