IMPROVEMENTS IN OR RELATING TO ORGANIC COMPOUNDS

Abstract

A fragrance precursor represented by the formula 1

##STR00001##

wherein

X and Y together represent a double bond to a carbon atom bearing R.sub.1 and R.sub.2, with R.sub.1═H, methyl, acetyl or C.sub.1—C.sub.3 alkoxycarbonyl (e.g. ethoxycarbonyl); and R2=phenyl optionally substituted with up to 3 (i.e. 0, 1, 2 or 3) groups selected from C.sub.1—C.sub.4 alkyl (e.g. methyl, ethyl, iso-propyl, tert-butyl), vinyl, hydroxy, C.sub.1—C.sub.3 alkoxy (e.g. ethoxy), and —O—CH.sub.2—O—, e.g. R.sub.2 is benzo[d][1,3]dioxol-5-yl, 4-methylphenyl, 4-methoxyphenyl, 4-vinylphenyl or 3-ethoxy-4-hydroxyphenyl or

R2=naphthyl, (naphthyl) methyl, 1,1,2,4,4,8-hexamethyl-1,2,3,4-tetrahydronaphthalen-7-yl, or 1,1,2,4,4,-penta methyl-1,2,3,4-tetrahydronaphthalen-7-yl or

R2=COR3, wherein R3 is H, C1-C10 alkoxy (e.g. ethoxy, 1-(3,3-dimethylcyclohexyl)ethoxy), C1-C4 alkyl (e.g. methyl, ethyl, propyl, iso-propyl, tert-butyl), e.g. R2 is formyl, acetyl, ethoxycarbonyl, 1-(3,3-dimethylcyclohexyl)ethoxycarbonyl; or wherein

X is OR4, with R4 being H or alkyl, and

Y is OR5, with R5 being alkyl,

useful as a perfume ingredient.

Claims

1. A fragrance precursor according to the formula 1 ##STR00007## wherein X and Y together represent a double bond to a carbon atom bearing R.sub.1 and R.sub.2, R.sub.1 is H, methyl, acetyl or C.sub.1—C.sub.3 alkoxycarbonyl (e.g. ethoxycarbonyl); and R2 is phenyl optionally substituted with up to 3 groups selected from C.sub.1—C.sub.4 alkyl, vinyl, hydroxy, C.sub.1—C.sub.3 alkoxy, and —O—CH.sub.2—O—, or R.sub.2 is naphthyl, (naphthyl)methyl, 1,1,2,4,4,8-hexamethyl-1,2,3,4,-tetrahydronaphthalen-7-yl, or 1,1,2,4,4,-pentamethyl-1,2,3,4-tetrahydronaphthalen-7-yl or R.sub.2 is COR.sub.3, wherein R.sub.3 is H, C.sub.1—C.sub.10 alkoxy 1-(3,3-dimethylcyclohexyl)ethoxy), C.sub.1—C.sub.4 alkyl or wherein X is OR.sub.4, wherein R.sub.4 is H or alkyl, and Y is OR.sub.5, whereing R.sub.5 is alkyl.

2. A fragrance precursor according to claim 1 selected from the group consisting of ethyl 2-acetyl-5-(4-isobutyl-2-methylphenyl)pent-2-enoate, and, 4-isobutyl-1-(4-(4-methoxyphenyl)but-3-en-1-yl)-2-methylbenzene.

3. A perfume ingredient comprising a fragrance precursor according to claim 1.

4. The perfume ingredient according to claim 3 which is adapted to release an ingredient with muguet odour characteristics.

5. A perfume composition comprising a fragrance precursor according to claim 1.

6. A perfume composition according to claim 5 that is free of aryl-substituted propanals, that are unsubstituted on the aryl ring at a position ortho to the substituent bearing the aldehyde functionality, in particular Lilial™.

7. A perfume composition according to claim 5 3-(4-isobutyl-2-methylphenyl)propanal.

8. A perfume composition according to claim 5 comprising one or more additional fragrance ingredients.

9. A perfume composition according to, which is adapted to release an ingredient with muguet odour characteristics.

10. A personal care or household care composition comprising a fragrance precursor according to claim 1.

11. A method of imparting a muguet odour characteristic to a perfume composition comprising the step of: adding to said composition at least a fragrance precursor according to claim 1.

12. The fragrance precursor of claim 1, wherein R.sub.2 is benzo[d][1,3]dioxol-5-yl, 4-methylphenyl, 4-methoxyphenyl, 4-vinylphenyl or 3-ethoxy-4-hydroxyphenyl.

13. The fragrance precursor of claim 1, wherein R.sub.2 is R2 is formyl, acetyl, ethoxycarbonyl, 1-(3,3-dimethylcyclohexyl)ethoxycarbonyl.

14. A perfume ingredient comprising a fragrance precursor according to claim 2.

15. A perfume composition comprising a fragrance precursor according to claim 2.

16. A personal care or household care composition comprising a fragrance precursor according to claim 2.

17. A method of imparting a muguet odour characteristic to a perfume composition comprising the step of: adding to said composition at least a fragrance precursor according to claim 2

18. The perfume ingredient according to claim 14 which is adapted to release an ingredient with muguet odour characteristics.

Description

EXAMPLE 1

Ethyl 2-acetyl-5-(4-isobutyl-2-methylphenyl)pent-2-enoate

[0113] ##STR00005##

[0114] A mixture of 3-(4-isobutyl-2-methylphenyl)propanal (20.4 g, 100 mmol), ethyl acetoacetate (12.2 g, 94 mmol) and 2-methyl-2-amino 1-propanol (0.45 g, 5 mol %) was vigorously shaken until a homogeneous solution was formed, then left to stand in a closed bottle for 30 h. The now turbid mixture was diluted with MTBE, washed with brine/water (1:1), sat. aq. NaHCO.sub.3, brine/water (1:1) and brine. The organic layer was dried (MgSO.sub.4), filtered and the filtrate was concentrated. Residual traces of solvent were removed by drying at 0.1 mbar/50° C. for 1 h to yield 28.0 g (crude yield 88%) of a yellow oil containing 73% of ethyl 2-acetyl-5-(4-isobutyl-2-methylphenyl)pent-2-enoate as a mixture of E-/Z-isomers.

[0115] .sup.1H NMR (CDCl.sub.3, 400 MHz); sum of (E/Z) isomers: δ=7.22−6.74 (m, 4H), 4.49-4.15 (m, 2H), 2.85-2.75 (m, 1H), 2.69-2.53 (m, 1H), 2.50-2.40 (m, 2H), 2.37-2.20 (m, 8H), 1.95-1.82 (m, 1H), 1.40-1.28 (m, 3H), 0.95 and 0.94 (2d, J =6.6 Hz, together 6H) ppm. .sup.13C-NMR (CDCl.sub.3, 100 MHz); mixture of (E/Z) isomers: δ=200.7 (s), 194.9 (s), 166.1 (s), 164.2 (s), 147.5 (d), 147.2 (d), 139.7 (s), 137.2 (s), 135.5 (s), 135.2 (s), 131.0 (d), 128.5 (d), 128.2 (d), 126.7 (d), 61.0 (t), 60.9 (t), 44.9 (t), 44.8 (2t), 31.4 (t), 30.4 (t), 30.0 (t), 30.0 (d), 22.3 (q), 19.2 (q), 14.0 (q) ppm. MS (EI); major isomer: m/z (%)=316 (M.sup.+.Math., 2), 298 (1), 270 (5), 242 (5), 227 (4), 186 (7), 161 (100), 119 (38), 105 (14), 91 (10), 43 (37).

[0116] Odour description: floral green fatty muguet cyclamen, fatty buttery, green aldehydic, privet

EXAMPLE 2

4-Isobutyl-1-(4-(4-methoxyphenyl)but-3-en-1-yl)-2-methylbenzene

[0117] ##STR00006##

[0118] Potassium t-butylat (1 M in THF, 9.1 mL) was added to a solution of (4-methoxybenzyl)-triphenylphosphonium bromide (4.21 g, 9.09 mmol) in THF (9 mL) at 0° C. After the red suspension was stirred at 0° C. for 10 min, 3-(4-isobutyl-2-methylphenyl)propanal (2.04 g, 10.0 mmol) in THF (5 mL) was added at 0° C., and the mixture was stirred at 25° C. for 2 h. After addition of water, the aqueous layer was extracted with hexane (2x). The combined organic phases were washed with MeOH/water (4:1; 3x), dried (MgSO.sub.4), filtered and the filtrate was concentrated. The residue was purified by flash chromatography on SiO.sub.2 (hexane/EtOAc 199:1.fwdarw.99:1) and dried in the “Kugelrohr” oven under HV to yield 1.16 g (41%, purity 99%) of the title compound as a colorless oil. The product consists of a mixture of E-/Z-isomers (rat1.8:1).

[0119] .sup.1H NMR (CDCl.sub.3, 400 MHz); mixture of (E/Z) isomers: δ=7.33−7.30 (m, 2H), 7.24-7.20 (m, 2H), 7.12 (d, J=7.3 Hz, 1H), 7.09 (d, J=7.6 Hz, 1H), 6.98-6.94 (m, 4H), 6.90-6.86 (m, 4H), 6.43 (dt, J=11.5, 1.7 Hz, 1H), 6.42 (d, J=15.9 Hz, 1H), 6.20 (dt, J=15.9, 6.9 Hz, 1H), 5.69 (dt, J=11.7, 7.1 Hz, 1H), 3.84 (s, 3H), 3.84 (s, 3H), 2.79-2.74 (m, 4H), 2.67-2.60 (m, 2H), 2.52-2.47 (m, 2H), 2.46 (d, J=7.1 Hz, 2H), 2.45 (d, J=7.1 Hz, 2H), 2.35 (s, 3H), 2.31 (s, 3H), 1.89 (nonet, J=6.9 Hz, 1H), 1.88 (nonet, J=6.9 Hz, 1H), 0.95 (d, J=6.6 Hz, 6H), 0.94 (d, J=6.6 Hz, 6H) ppm. .sup.13C-NMR (CDCl.sub.3, 100 MHz); mixture of (E/Z) isomers: δ=158.7 (s), 158.2 (s), 139.3 (s), 139.3 (s), 137.2 (s), 137.1 (s), 135.5 (s), 135.4 (s), 131.0 (2d), 130.6 (d), 130.6 (s), 130.3 (s), 129.9 (2d), 129.5 (d), 128.7 (d), 128.5 (d), 128.5 (d), 128.1 (d), 127.0 (2d), 126.6 (d), 126.6 (d), 113.9 (2d), 113.5 (2d), 55.2 (q), 55.2 (q), 45.0 (t), 45.0 (t) 33.7 (t), 33.1 (t), 33.0 (t), 30.2 (2d), 29.3 (t), 22.4 (4q), 19.4 (2q) ppm. MS (EI); Z-isomer: m/z (%)=308 (M.sup.+.Math., 3), 161 (6), 148 (11), 147 (100), 131 (3), 119 (8), 118 (7), 117 (6), 115 (8), 103 (4), 91 (11), 43 (4); E-isomer: m/z (%)=308 (M.sup.+.Math., 3), 161 (5), 148 (11), 147 (100), 131 (3), 119 (8), 118 (7), 117 (6), 115 (8), 103 (4), 91 (10), 43 (3).

[0120] Odour description: floral muguet, green fatty cyclamen, floral fruity mimosa