Pyran derivatives, their preparation and use thereof in perfumery

Abstract

A process of preparing a compound of formula (I) wherein R represents a linear or branched C5 alkyl group, as well as the use of such compounds in a fragrant and/or flavoring composition. ##STR00001##

Claims

1. A process of preparing a compound of formula (I) ##STR00013## wherein R represents a linear or branched C5 alkyl group, the process comprising reacting a compound of formula (III) ##STR00014## wherein R is as defined in respect of formula (I), with a compound of formula (IV) ##STR00015## in the presence of an acid and in the absence of water, the reaction being carried out in an organic solvent selected from the group consisting of toluene, xylene, trimethylbenzene, cyclohexane, and methylcyclohexane, at a temperature of about 70 C. to reflux; wherein the acid is H.sub.2SO.sub.4, sulfonic acid or ZnCl.sub.2 supported on clay.

2. The process according to claim 1, wherein the compound of formula (III) is selected from the group consisting of 2-ethyl-butyraldehyde and hexanal.

3. The process according to claim 1 wherein the reaction is carried out at a temperature of about 80 C. to 90 C.

4. The process according to claim 1 wherein the reaction is carried out at a temperature of about 80 C.

Description

Example 1

Preparation of 2-(1-ethyl-propyl)-4-methyl-tetrahydro-2H-pyran-4-ol

(1) A 2M solution of 2-ethyl-butyraldehyde (1 eq.) and 3-methyl-3-buten-1-ol (1 eq.) in toluene with 10% weight of Montmorillonite K10 is heated under reflux or at 80 C. for 2 hours. After cooling down, the mixture is filtered on a frit and the solvents are evaporated. The crude mixture is then distilled with a Vigreux column under reduced pressure. To get a purer compound, a fine distillation with a packed column can be also performed.

(2) The results are summarised in the table below.

(3) TABLE-US-00001 Conditions Temp. of reaction: reflux Temp. of reaction: 80 C. Temp. of reaction: 80 C. 2-ethyl-butyraldehyde: 2-ethyl-butyraldehyde: 2-ethyl-butyraldehyde: 200 g (2 mol) 21 g (0.21 mol) 100 g (1 mol) 385 g crude product (Pyrans 37.6 g crude product (Pyrans 205 g crude product (Pyrans 33%, pyranols 51%, ethers 9%) 11%, pyranols 67%, ethers 15%) 15%, pyranols 58%, ethers 18%) Crude yield (pyranols) = 53% Crude yield (pyranols) = 64% Crude yield (pyranols) = 64% Fractions Bp Mass/Product(s) Bp Mass/Product(s) Bp Mass/Product(s) I 77-80 C./ 80 g .fwdarw. 68 C./ 5 g .fwdarw. 60 C./ 8.6 g 1 kPa Pyrans 800 Pa Pyrans 667 Pa Pyrans (90% (54%) (54%) purity) Pyranols Pyranols (35.7%) (35.7%) II 85-100 C./ 79 g 75-90 C./ 18.2 g 96-98 C./ 87 g 1 kPa Pyrans 667 Pa Pyranols 667 Pa Pyranols (26%) (93% (95% Pyranols purity) purity) (67%) III 105 C./ 104 g 105 C./ 5.2 g 109-115 C./ 7.5 g 800 Pa Pyranols 667 Pa Pyranols 667 Pa Pyranols (90%; (41%) (73%) purity) Pyranyl Pyranyl ethers (54%) ethers (22%)

(4) The 2-(1-ethyl-propyl)-4-methyl-tetrahydro-pyran-4-ol thus obtained is usually a 50:50 mixture of cis/trans isomers.

(5) Odour: Top notes: Green, floral, Lily of the valley, rosy, Rose oxide. Dried down notes: Lily of the valley, lemony, musky.

(6) Tenacity on the blotter: 48 hours; more than Rose oxide.

(7) IR (film, cm-1): 592w, 633w, 882w, 936w, 1005w, 1059w, 1083m, 1107m, 1127m, 1166m, 1257w, 1346w, 1379m, 1464m, 2876s, 2963s, 3407(br)m.

(8) 1.sup.st Isomer:

(9) .sup.1H-NMR (200 MHz, CDCl.sub.3): (ppm) 0.86 (t, J=7.1 Hz, 6H); 1.18-1.74 (m, 9H); 1.25 (s, 3H); 3.58 (ddd, J=2.4 Hz, J=5.2 Hz, J=11.3 Hz, 1H); 3.71 (dt, J=2.5 Hz, J=11.9 Hz, 1H); 3.75-3.90 (m, 1H).

(10) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 11.50 & 11.55; 21.46; 32.01; 38.86; 41.11; 45.65; 63.80; 68.06; 74.40.

(11) MS [e/m (%)]: 186 (M+), 115 (41), 97 (10), 71 (97), 69 (86), 58 (19), 55 (17), 43 (100), 41 (25).

(12) 2.sup.nd Isomer:

(13) .sup.1H-NMR (200 MHz, CDCl.sub.3): (ppm) 0.86 (t, J=7.1 Hz, 6H); 1.18-1.74 (m, 9H); 1.31 (s, 3H); 3.24 (ddd, J=2.1 Hz, J=5 Hz, J=11.4 Hz, 1H); 3.38 (dt, J=3 Hz, J=12 Hz, 1H); 3.95 (ddd, J=1.9 Hz, J=5 Hz, J=11.9 Hz, 1H).

(14) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 11.44 & 44.59; 21.58; 25.39; 40.81; 42.91; 45.71; 65.55; 69.27; 77.02.

(15) MS [e/m (%)]: 186 (M+), 115 (34), 71 (87), 69 (71), 58 (13), 55 (15), 43 (100), 41 (23).

Example 2

Preparation of 2-(1-ethyl-propyl)-4-methyl-tetrahydro-2H-pyran-4-ol

(16) The compound is prepared by treating 2-ethylbutyraldehyde and 3-methyl-3-buten-1-ol with a 2 molar equivalent 85:15 mixture of acetic acid/trifluoroacetic acid. The resulting mixture is then treated by KOH in refluxing ethanol to give the pyranol.

(17) Characterization: as Example 1.

Example 3

4-Methylene-2-(pentan-3-yl)-tetrahydro-2H-pyran (II-Aa), 4-methyl-2-(pentan-3-yl)-5,6-dihydro-2H-pyran (II-Ab) et 4-methyl-2-(pentan-3-yl)-3,6-dihydro-2H-pyran (II-Ac)

(18) Method A:

(19) The compound is prepared by dehydration of the corresponding pyranol (Example 1) in the presence of catalytic amount of PISA in refluxing toluene, using a Dean-Stark apparatus.

(20) Method B:

(21) The compound is also directly prepared by refluxing a toluene solution of 2-ethylbutyraldehyde (1 mol) and 3-methyl-3-buten-1-ol with catalytic amount of an acid. After completion of the reaction, the reaction mixture is cooled down, washed with saturated aqueous sodium bicarbonate solution and with brine. The organic phase is dried over magnesium sulphate and filtrated. The solvents are evaporated and the crude product is purified by distillation. The different results for method B are summarised in the table below.

(22) TABLE-US-00002 Isomers [Ald.] Recovered ratio Entry (mol .Math. l.sup.1) Alcohol Acid Time Bp mass Purity (a:b:c) Yield 1 2M 2 mol PTSA 3.5 hrs 105-108 C./ 90.5 g 91% 60:17:23 51% (5% weight) 4.4 kPa 2 2M 2 mol PTSA 3.5 hrs 73-75 C./ 132 g 83% 54:18:28 65% (5% weight) 800 Pa 3 3M 2 mol PTSA 12 days 74 C./ 89 g 89% 5:21:79 45% (5% weight) 800 Pa 4 3M 1.5 mol H.sub.2SO.sub.4 2 days 78 C./ 82 g 84% 3:13:94 41% (5% weight) 800 Pa 5 3M 1 mol H.sub.2SO.sub.4 2 days 92 C./ 67 g 98% 9:18:73 40% (2% weight) 2.0 kPa 6.sup.(*.sup.) 1M 1.2 mol PTSA 1 day 94-96 C./ 116 g 88% 3:21:76 61% (2% weight) 2.3 kPa .sup.(*.sup.)The 3-methyl-3-buten-1-ol is added dropwise to the refluxing solution of aldehyde with acid.

(23) The recovered product consists in a mixture of isomers (II-Aa), (II-Ab) and (II-Ac).

(24) Odour: Top notes: green, rosy, metallic, fruity (mango, bergamote) petitgrain, rose oxide, Cologne. Dry down notes: none.

(25) Fine distillation with a packed column gives very enriched fractions of the different pyrans a, b or c. Especially a and c are obtained as pure compounds.

(26) IR (film, cm.sup.1): 887m, 1061m, 1095s, 1112m, 1379m, 1462m, 1654m, 2846m, 2875s, 2936s, 2962s.

4-Methylene-2-(pentan-3-yl)-tetrahydro-2H-pyran (II-Aa)

(27) .sup.1H-NMR (500 MHz, CDCl.sub.3): (ppm) 0.85 (t, J=7.5 Hz, 3H); 0.86 (t, J=7.4 Hz, 3H); 1.18-1.52 (m, 5H); 2.01 (t, J=12.2 Hz, 1H); 2.09 (dd br, J=0.8 Hz, J=13.3 Hz, 1H); 2.15 (d br, J=13.1 Hz, 1H); 2.25 (dt, J=5.6 Hz, J=12.8 Hz, 1H); 3.16 (ddd, J=2.2 Hz, J=5.5 Hz, J=11.2 Hz, 1H); 3.30 (ddd, J=2.5 Hz, J=10.5 Hz, J=11.5 Hz, 1H); 4.04 (dd, J=5.6 Hz, J=10.8 Hz, 1H); 4.68 (s, 2H).

(28) .sup.13C-NMR (125 MHz, CDCl.sub.3): (ppm) 11.4; 21.4 & 21.5; 35.4; 37.8; 45.8; 68.9; 80.5; 108.1; 145.4.

(29) MS [e/m (%)]: 168 (M+, 4), 97(100), 96(30), 69(19), 68(21), 67(54), 55(16), 53(16), 43(16), 41(28).

(30) Odour: Green (parsley), fruity (pear, green pear peel), rose oxide, petitgrain.

4-Methyl-2-(pentan-3-yl)-5,6-dihydro-2H-pyran (II-Ab)

(31) .sup.1H-NMR (500 MHz, CDCl.sub.3): (ppm) 0.87 (d, J=7.5 Hz, 3H); 0.87 (t, J=6.0 Hz, 3H); 1.18-1.52 (m, 5H); 1.67 (s, 3H); 1.79 (dt, J=5.5 Hz, J=13.1 Hz, 1H); 2.16-2.24 (m, 1H); 3.55 (dt, J=3.6 Hz, J=10.9 Hz, 1H); 3.96 (ddd, J=1.3 Hz, J=5.9 Hz, J=11.1 Hz, 1H); 4.0-41 (m, 1H); 5.28 (s, 1H).

(32) .sup.13C-NMR (125 MHz, CDCl.sub.3): (ppm) 12.0 & 12.1; 21.9 & 22.3; 23.2; 30.2; 46.2; 64.0; 75.5; 122.7; 132.7.

(33) MS [e/m (%)]: 168 (M+, 1), 97(100), 43(12), 41(16).

4-Methyl-2-(pentan-3-yl)-3,6-dihydro-2H-pyran (II-Ac)

(34) .sup.1H-NMR (500 MHz, CDCl.sub.3): (ppm) 0.87 (t, J=7.5 Hz, 6H); 1.2-1.28 (m, 1H); 1.27-1.35 (m, 1H); 1.35-1.47 (m, 1H); 1.45-1.55 (m, 2H); 1.68 (s, 3H); 1.71-1.78 (m, 1H); 1.97-1.06 (m, 1H); 3.38 (ddd, J=3.3 Hz, J=6.1 Hz, J=10.0 Hz, 1H); 4.11 (q, J=15.8 Hz, 2H); 5.39 (m, 1H).

(35) .sup.13C-NMR (125 MHz, CDCl.sub.3): (ppm) 11.2 & 11.3; 21.2 & 21.3; 23.1; 32.9; 45.6; 66.2; 75.4; 119.6; 132.2.

(36) MS [e/m (%)]: 168 (M+, 5), 124(9), 97(62), 71(17), 69(100), 68(48), 67(32), 55(27), 53(17), 43(40), 41(50).

Example 4

2-(1-ethyl-propyl)-4-methyl-tetrahydro-2H-pyran-4-yl acetate

(37) The compound is prepared by reacting the corresponding pyranol (Example 1) with acetic anhydride at 60 C. for 2-3 hours. The excess acetic anhydride and acetic acid are then removed by distillation under reduced pressure. The so obtained product is diluted in t-butyl methyl ether and the solution is washed with water, with saturated aqueous sodium bicarbonate solution and with brine. After drying over magnesium sulphate, the solvent is removed by evaporation.

(38) The crude product is purified by distillation to give 2-(1-ethyl-propyl)-4-methyl-tetrahydro-2H-pyran-4-yl acetate as a mixture of isomers.

(39) Odour: Top notes: Green, hesperidic, fatty, spicy. Dry down notes: Woody, spicy (carvi), powdery/sweet (methyl ionone, ambery, vanilla).

(40) Bp=72 C./0.51 torr.

(41) IR (film, cm.sup.1): 1020m, 1083m, 1109m, 1144m, 1236s, 1369m, 1464m, 1736s, 2877m, 2935m, 2964s.

(42) 1.sup.st Isomer:

(43) .sup.1H-NMR (200 MHz, CDCl.sub.3): (ppm) 0.86 (t, J=7.2 Hz, 6H); 1.10-1.65 (m, 7H); 1.61 (s, 3H); 1.86 (dt, J=5.3 Hz, J=12.9 Hz, 2H); 1.7-2.3 (m, 2H); 2.01 (s, 3H); 3.35-3.50 (m, 1H); 3.58 (ddd, J=2.1 Hz, J=11.7 Hz, J=12.5 Hz, 1H); 3.82 (ddd, J=1.2 Hz, J=5.4 Hz, J=11.7 Hz, 1H).

(44) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 11.41 & 11.59; 21.56 & 21.65; 21.63; 22.30; 36.50; 38.35; 45.48; 63.61; 74.25; 79.51; 170.39.

(45) MS [e/m (%)]: 228 (M+), 97 (100), 69 (12), 55 (6), 43 (34), 41 (13).

(46) 2.sup.nd Isomer:

(47) .sup.1H-NMR (200 MHz, CDCl.sub.3): (ppm) 0.86 (t, J=7.2 Hz, 6H); 1.10-1.65 (m, 7H); 1.51 (s, 3H); 1.7-2.3 (m, 2H); 1.97 (s, 3H); 3.29 (ddd, J=1.6 Hz, J=4.6 Hz, J=11.9 Hz, 1H); 3.35-3.50 (m, 1H); 3.93 (ddd, J=1.7 Hz, J=5.2 Hz, J=12.1 Hz, 1H).

(48) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 11.49 & 11.56; 21.51; 22.48; 26.39; 37.82; 39.85; 45.73; 64.74; 76.06; 80.55; 170.27.

(49) MS [e/m (%)]: idem 1.sup.st isomer.

Example 5

Preparation of propionic acid 2-(1-ethyl-propyl)-4-methyl-tetrahydro-2H-pyran-4-yl ester

(50) Propionic acid 2-(1-ethyl-propyl)-4-methyl-tetrahydro-pyran-4-yl ester was prepared from the corresponding pyranol (Example 1 or 2) and propionic anhydride according to example 4. It is obtained as a 55:45 mixture of isomers.

(51) Odour: Myrrhe, roasted beans, not powerful.

(52) IR (film, cm-1): 1003w, 1082m, 1109m, 1142m, 1195s, 1257w, 1358w, 1379m, 1464m, 1734s, 2877m, 2938m, 2964s.

(53) Major Isomer:

(54) .sup.1H-NMR (200 MHz, CDCl.sub.3): (ppm) 0.85 (t, J=7.3 Hz, 6H); 1.11 (t, J=7.2 Hz, 3H); 1.15-1.48 (m, 5H); 1.48-1.60 (m, 2H); 1.50 (s, 3H); 1.95-2.05 (m, 1H); 2.15-2.37 (m, 4H); 3.35-3.55 (m, 2H); 3.82 (ddd, 1H, J=1.1 Hz, J=5.5 Hz, J=11.7 Hz).

(55) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 9.38; 11.37 & 11.58; 21.51; 26.44; 28.86; 36.54; 38.31; 45.45; 63.64; 74.17; 79.17; 173.66.

(56) MS [e/m (%)]: 242 (M+), 169 (2), 168 (2), 153 (2), 140 (5), 97 (100), 69 (15), 57 (17), 43 (43), 41 (13).

(57) Minor Isomer:

(58) .sup.1H-NMR (200 MHz, CDCl.sub.3, selected data): (ppm) 1.07 (t, J=7.0 Hz, 3H); 1.61 (s, 3H); 1.82 (dt, J=5.2 Hz, J=12.7 Hz, 2H); 2.05-2.15 (m, 2H); 2.15-2.3 (m, 1H); 3.22-3.5 (m, 1H); 3.55-3.65 (m, 1H); 3.93 (ddd, 1H, J=1.5 Hz, J=5.1 Hz, J=11.8 Hz).

(59) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 9.12; 11.46 & 11.53; 21.47 & 21.61; 21.69; 28.71; 37.86; 39.86; 45.71; 64.75; 76.05; 80.24; 173.66.

(60) MS [e/m (%)]: idem major isomer.

Example 6

Preparation of but-2-enoic acid 2-(1-ethyl-propyl)-4-methyl-tetrahydro-2H-pyran-4-yl ester and but-3-enoic acid 2-(1-ethyl-propyl)-4-methyl-tetrahydro-2H-pyran-4-yl ester

(61) The esters are prepared from the corresponding pyranol (Example 1 or 2) and crotonic anhydride according to example 4. They are obtained as a 80:20 mixture of isomers and can be separated by fine distillation.

(62) Odour: coffee, green nuts, spicy (fenugrec, liveche).

(63) IR (film, cm-1): 970m, 997m, 1060w, 1083m, 1104m, 1142m, 1188s, 1255m, 1295m, 1315m, 1379m, 1446m, 1462m, 1657m, 1717s, 2876m, 2935m, 2963s.

But-2-enoic acid 2-(1-ethyl-propyl)-4-methyl-tetrahydro-2H-pyran-4-yl ester

(64) The compound is obtained as a 95:5 E/Z mixture of enantiomers (ratio of cis/trans isomers: 50:50).

(65) Isomer 1 (E-Isomer):

(66) .sup.1H-NMR (200 MHz, CDCl.sub.3): (ppm) 0.84 (t, J=7.2 Hz, 6H); 1.10-1.67 (m, 7H); 1.52 (s, 3H); 1.85 (dd, J=1.7 Hz, J=6.9 Hz, 3H); 1.97-2.13 (m, 1H); 2.13-2.32 (m, 1H); 3.35-3.52 (m, 1H); 3.59 (dt, J=2.0 Hz, J=12.5 Hz, 1H); 3.81 (dd, 1H, J=4.7 Hz, J=11.6 Hz); 5.79 (qd, J=1.6 Hz, J=15.5 Hz, 1H); 6.88 (qd, J=6.9 Hz, J=15.4 Hz, 1H).

(67) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 11.38 & 11.59; 17.81; 21.51 (2C); 26.48; 36.57; 38.46; 45.46; 63.62; 74.19; 79.17; 124.11; 143.63; 165.61.

(68) Isomer 2 (E-Isomer):

(69) .sup.1H-NMR (200 MHz, CDCl.sub.3): (ppm) 0.85 (t, J=7.2 Hz, 6H); 1.10-1.55 (m, 6H); 1.64 (s, 3H); 1.83 (dd, J=1.7 Hz, J=6.9 Hz, 3H); 1.76-1.96 (m, 1H); 1.98-2.15 (m, 2H); 3.30 (ddd, J=1.5 Hz, J=4.5 Hz, J=11.9 Hz, 1H); 3.44 (dt, J=2.3 Hz, J=12.4 Hz, 1H); 3.93 (ddd, J=1.5 Hz, J=5.2 Hz, J=11.9 Hz, 1H); 5.75 (qd, J=1.5 Hz, J=15.4 Hz, 1H); 6.86 (qd, J=6.9 Hz, J=15.5 Hz, 1H).

(70) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 11.47 & 11.54; 17.74; 21.48 & 21.62; 21.71; 31.90; 39.87; 45.71; 64.74; 76.04; 80.26; 124.20; 143.56; 165.62.

(71) MS [e/m (%)]: (isomer 1 (Z or E)) 254 (M+, <1), 168 (2), 153 (2), 140 (6), 97 (100), 69 (34), 55 (6), 43 (13), 41 (21).

(72) MS [e/m (%)]: (isomer 2 (Z or E)) 254 (M+, <1), 97 (100), 69 (33), 55 (5), 43 (12), 41 (17).

But-3-enoic acid 2-(1-ethyl-propyl)-4-methyl-tetrahydro-2H-pyran-4-yl ester

(73) The compound is obtained as a 20:80 mixture of enantiomers.

(74) Minor Isomers:

(75) .sup.1H-NMR (200 MHz, CDCl.sub.3): (ppm) 0.84 (t, 6H, J=7.2 Hz); 1.10-1.25 (m, 3H); 1.25-1.70 (m, 3H); 1.50 (s, 3H); 1.94 (d, 1H, J=7.3 Hz); 2.0-2.35 (m, 2H); 3.04 (td, 2H, J=1.4 Hz, J=7.1 Hz); 5.07-5.12 (m, 1H); 5.15-5.22 (m, 1H); 5.80-6.02 (m, 1H).

(76) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 11.35 & 11.53; 21.47; 26.38; 36.44; 38.23; 40.58; 45.40; 63.54; 74.05; 79.89; 118.37; 130.56; 170.58.

(77) MS [e/m (%)]: 254 (M+, <1), 163 (13), 97 (100), 69 (53), 55 (8), 43 (15), 41 (32).

(78) Major Isomers:

(79) .sup.1H-NMR (200 MHz, CDCl.sub.3): (ppm) 0.85 (t, J=7.2 Hz, 6H); 1.10-1.55 (m, 6H); 1.61 (s, 3H); 1.76-1.96 (m, 1H); 1.98-2.31 (m, 2H); 3.0 (td, J=1.4 Hz, J=7.0 Hz, 2H); 3.22-3.40 (m, 1H); 3.40-3.52 (m, 1H); 3.87-3.99 (m, 1H); 5.05-5.21 (m, 2H); 5.80-6.02 (m, 1H).

(80) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 11.44 & 11.53; 21.60 & 21.66; 26.48; 37.78; 39.79; 40.32; 45.68; 64.71; 76.03; 80.94; 118.16; 130.62; 170.60.

(81) MS [e/m (%)]: idem minor.

Example 7

2-(1-ethyl-propyl)-4-methyl-tetrahydro-2H-pryan

(82) The compound is prepared by hydrogenation, in the presence of Pd on charcoal, of the corresponding mixture of pyrans (Example 3).

(83) It consists in a mixture of two diastereoisomers: cis/trans (72:28).

(84) Odour: Top notes: minty, cocoa powder, musky. Dry down notes: musky, dusty.

(85) Bp=76-78 C./1.5 kPa.

(86) Cis-Isomer:

(87) .sup.1H-NMR (CDCl.sub.3, 200 MHz): (ppm) 0.80-0.95 (m, 9H); 1.10-1.70 (m, 9H); 3.18 (ddd, 1H, J=1.2 Hz, J=3.28 Hz, J=11.1 Hz); 3.35 (td, 1H, J=2.1 Hz, J=11.8 Hz); 3.97 (ddd, 1H, J=1.2 Hz, J=4.5 Hz, J=11.3 Hz).

(88) .sup.13C-NMR (CDCl.sub.3, 50 MHz): (ppm) 11.64, 21.67 & 21.76, 22.57, 30.67, 35.04, 36.98, 46.14, 68.32, 79.30.

(89) Trans-Isomer:

(90) .sup.1H-NMR (CDCl.sub.3, 200 MHz, selected data): (ppm) 1.04 (d, 3H, J=7.1 Hz); 1.65-1.90 (m, 2H); 1.92-2.12 (m, 1H); 3.40-3.95 (m, 3H).

(91) .sup.13C-NMR (CDCl.sub.3, 50 MHz): (ppm) 11.24 & 11.27, 18.44, 21.29 & 21.47, 25.02, 32.33, 34.10, 44.47, 62.92, 73.55.

(92) IR (film, cm.sup.1): 1082 s, 1097 s, 1174 m, 1458 m, 2840 s, 2874 s, 2928 s, 2959 s.

(93) MS [e/m (%)]: (cis) 170(M+), 169(1), 99(100), 81(15), 55(22), 43(35), 41(16).

(94) MS [e/m (%)]: (trans) ibid.

Example 8

Preparation of 4-methyl-2-(1-pentyl)-tetrahydro-2H-pyran-4-ol

(95) The compound is prepared from hexanal and 3-methyl-3-buten-1-ol according to example 1. It is obtained as a mixture of isomers.

(96) Odour: Top notes: Green (grass, violet leaves), fruity (apple, pineapple), rosy. Dry down notes: more floral (jasminic, rosy), fruity.

(97) IR (film, cm.sup.1): 1087m, 1111s, 1173m, 1259m, 1378m, 1463m, 2861s, 2933s, 2958s, 3431m (br).

(98) Major Isomer:

(99) .sup.1H-NMR (200 MHz, CDCl.sub.3): (ppm) 0.85 (t, J=6.4 Hz, 3H); 1.2-1.8 (m, 12H); 1.21 (s, 3H); 3.39 (dt, J=2.9 Hz, J=12.0 Hz, 1H); 3.50-3.65 (m, 1H); 3.75-3.87 (m, 1H).

(100) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 13.99; 22.56; 25.14; 31.76; 31.89; 36.14; 38.71; 44.63; 63.56; 67.82; 72.92.

(101) MS [e/m (%)]: 186 (M+), 115 (28), 112 (23), 97 (21), 83 (22), 71 (90), 69 (71), 58 (31), 55 (26), 43 (100), 41 (31).

(102) Minor Isomer:

(103) .sup.1H-NMR (200 MHz, CDCl.sub.3, selected data): (ppm) 1.29 (s, 3H); 3.17-3.32 (m, 1H); 3.72 (dt, J=2.4 Hz, J=11.5 Hz, 1H); 3.93 (ddd, J=1.8 Hz, J=5.0 Hz, J=11.9 Hz, 1H).

(104) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 13.99; 22.56; 25.17; 25.38; 31.83; 36.30; 40.63; 46.57; 65.35; 68.82; 75.87.

(105) MS [e/m (%)]: 186 (M+), 115 (38), 71 (92), 69 (68), 58 (25), 55 (20), 43 (100), 41 (27).

Example 9

Preparation of 4-methylene-2-(1-pentyl)-tetrahydro-2H-pyran (II-Ba), 4-methyl-6-(1-pentyl)-3,6-dihydro-2H-pyran (II-Bb) and 4-methyl-2-(1-pentyl)-3,6-dihydro-2H-pyran (II-Bc)

(106) A (4:33:63) mixture of 4-methylene-2-pentyl-tetrahydro-pyran (II-Ba), 4-methyl-6-pentyl-3,6-dihydro-2H-pyran (II-Bb) and 4-methyl-2-pentyl-3,6-dihydro-2H-pyran (II-Bc) is obtained from 3-methyl-3-buten-1-ol and hexanal according to example 3 (Method B, specific conditions according to entry 6). The isomers can be separated by fine distillation.

(107) Odour: Top notes: Hesperidic (petitgrain, mandarine), green, rosy, metallic. Dry down notes: Powerful, green, hesperidic, floral, rosy, celery.

(108) IR (film, cm.sup.1): 1110m, 1140m, 1381m, 1457m, 2858m, 2931s, 2959s.

4-methylene-2-(1-pentyl)-tetrahydro-2H-pyran (II-Ba)

(109) .sup.1H-NMR (200 MHz, CDCl.sub.3, selected data): (ppm) 4.69 (m, 2H).

(110) .sup.13C-NMR (50 MHz, CDCl.sub.3, selected data): (ppm) 68.65, 78.83, 108.1.

4-methyl-6-(1-pentyl)-3,6-dihydro-2H-pyran (II-Bb)

(111) .sup.1H-NMR (200 MHz, CDCl.sub.3): (ppm) 0.87 (t, J=6.3 Hz, 3H), 1.2-1.6 (m, 8H), 1.67 (br s, 3H), 2.0-2.4 (m, 2H), 3.59 (ddd, J=4.0 Hz, J=10.1 Hz, J=11.2 Hz, 1H), 3.97 (ddd, J=2.3 Hz, J=5.9 Hz, J=11.1 Hz, 2H), 5.28-5.34 (m, 1H).

(112) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 14.03, 23.12, 25.03, 30.10, 31.95, 35.67, 35.92, 63.51, 74.03, 124.16, 132.01.

4-methyl-2-(1-pentyl)-3,6-dihydro-2H-pyran (II-Bc)

(113) .sup.1H-NMR (200 MHz, CDCl.sub.3): (ppm) 0.88 (t, J=6.3 Hz, 3H), 1.2-1.6 (m, 8H), 1.67 (br s, 3H), 1.65-2.0 (m, 2H), 3.32-3.51 (m, 1H), 4.05-4.15 (m, 2H), 5.34-5.43 (m, 1H).

(114) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 14.03, 22.61, 22.96, 25.16, 31.91, 395.92 (2C), 65.86, 73.78, 119.71, 131.81.

(115) MS [e/m (%)]: (II-Ba) 168 (M+, 2), 97 (100), 68 (35), 67 (81), 55 (21), 53 (19), 41 (29).

(116) (II-Bb) 168 (M+), 167 (1), 153 (3), 112 (12), 97 (100), 55 (10), 43 (14), 41 (21).

(117) (II-Bc) 168 (M+, 12), 99 (17), 97 (44), 71 (40), 69 (79), 68 (100), 67 (61), 56 (18), 55 (38), 53 (26), 43 (29), 41 (67), 39 (23).

Example 10

Preparation of acetic acid 4-methyl-2-(1-pentyl)-tetrahydro-2H-pyran-4-yl ester

(118) The compound is prepared by treating the corresponding pyranol (example 8) with acetic anhydride, according to example 4.

(119) It is obtained as a 80:20 mixture of isomers.

(120) Odour: Top notes: Green, woody, spicy. Dry down notes: Fruity (rhubarb), floral (violet), woody-ambery-spicy (Timberol, Trimofix).

(121) IR (film, cm.sup.1): 606w, 808w, 940w, 1019m, 1045w, 1087m, 1112m, 1145m, 1183m, 1203w, 1238s, 1369m, 1437w, 1462m, 1737s, 2861m, 2932s, 2957s.

(122) Major Isomer:

(123) .sup.1H-NMR (200 MHz, CDCl.sub.3): (ppm) 0.84 (t, J=6.5 Hz, 3H); 1.08-1.60 (m, 10H); 1.45 (s, 3H); 1.98 (s, 3H), 2.07-2.25 (m, 2H); 3.33-3.48 (m, 1H); 3.56 (dt, J=2.0 Hz, J=12.5 Hz, 1H); 3.70-3.80 (m, H).

(124) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 19.95; 22.24; 22.51; 25.05; 26.13; 31.86; 35.96; 36.20; 42.02; 63.31; 72.72; 79.18; 170.29.

(125) Minor Isomer:

(126) .sup.1H-NMR (200 MHz, CDCl.sub.3, selected data): (ppm) 1.60-1.70 (m, 1H); 1.75-1.90 (m, 1H); 1.93 (s, 3H); 3.77-3.83 (m, 1H).

(127) .sup.13C-NMR (50 MHz, CDCl.sub.3): (ppm) 19.95; 22.24; 22.51; 25.11; 31.71; 31.86; 36.14; 38.69; 44.62; 63.54; 72.84; 79.97; 170.16.

Example 11

Fragrance Composition Containing the Pyranol Obtained in Example 1

(128) A Lily of the valley type accord is prepared from the following ingredients:

(129) TABLE-US-00003 A B NERYL ACETATE 30 30 BENZYL ACETATE 10 10 CITRONELLYL ACETATE 16 16 GERANYL ACETATE 50 50 STYRALLYL ACETATE 5 5 BENZYLIQUE ALCOOL 30 30 PHENYLETHYL ALCOOL 50 50 STYRALLIQUE ALCOOL 3 3 HEXYLCINNAMIQUE ALDEHYDE 90 90 CYCLAMEN ALDEHYDE 17 17 PEONILE 67 67 CASSIS BASE 345F 25 25 CITRONELLOL PUR BBA 60 60 DIHYDROMYRCENOL 50 50 DIMETOL 12 12 ETHYL LINALOL 25 25 PENTALIDE 12 12 METHYL DIHYDROJASMONATE 50 50 HELIONAL 50 50 LILIAL 70 70 MUSC T 10 10 ORANGE TERPENES 10 10 TERPINEOL BI RECTIFIE 25 25 VERDENOL 8 8 AMBRETTOLIDE 2 2 EUCALYPTOL 1 1 HELIOTROPINE 3 3 HEXENOL CIS 3 3 3 LINALOL 16 16 DPG 0 200 Pyranol (Example 1) 200 0 TOTAL 1000 1000

(130) These 2 compositions (A, B), containing (A) or not (B) the pyranol from example 1, were used in a textile softener at usual dilution, known to the person of the art. The addition of the pyranol in formula A increases considerably the tenacity of the perfume on dried textiles. It brings a more floral-green note, very natural, imparting a fresher sensation to the textile.

Example 12

Fragrance Composition Containing the Pyranol Obtained in Example 1

(131) A Lily of the valley type accord, respecting hypoallergenic constraints, is prepared from the following ingredients:

(132) TABLE-US-00004 PHENYLETHYL ALCOOL PURISSIME 180 DIMETHYLPHENYLETHYLCARBINOL 26 METHYL DIHYDROJASMONATE 490 INDOL 3 IONONE ALPHA 10 TERPINEOL DROIT CRISTALLISE VMF 15 HEXYL ACETATE 4 ALDEHYDE C12 LAURIQUE 10% TEC 2 HEXENYL CIS 3 ACETATE 1 STYRALLYL ACETATE 1 FLORHYDRAL 3 CITRONELLYLOXYACETALDEHYDE 5 FLORALOZONE 5 PHENYLACETIQUE GLYCEROACETAL 7 UNDECAVERTOL 2 VELOUTONE 1 POLYSANTOL 3 CINNAMYL ACETATE 2 PHENYLETHYL ACETATE 3 INDOLAROME 1 DUPICAL 5 DPG 131 Pyranol (Example 1) 100 TOTAL 1000

(133) Adding the pyranol to the formula brings power to the fragrance and confers to the accord a nice greener, floral, Lily of the valley note.