PRODUCTION OF FARNESOL

Abstract

The present invention relates to an improved way for the production of farnesol.

Claims

1. A process for the production of the compound of formula (I) ##STR00011## wherein step (1) the compound of formula (II) ##STR00012## is reacted to a compound (III) by a rearrangement process in the presence of at least one mononuclear metal catalyst ##STR00013## and wherein step (2) the compound of formula (II) is reduced to a compound of formula (I).

2. Process according to claim 1, wherein step (1) the reaction is carried out in the presence of at least one catalyst chosen from the group consisting of ##STR00014##

3. Process according to claim 1, wherein the substrate (compound of formula (II) to catalyst ratio, which based on weight, is 10:1 to 500:1.

4. Process according to claim 1, wherein step (1) the reaction is carried out in at least one solvent, which is non-polar aprotic.

5. Process according to claim 4, wherein the solvents are aliphatic solvents having a high boiling point (above 280 C.), as well as aromatic solvents, such as xylene or toluene.

6. Process according to claim 1, wherein the reaction of step (1) is carried out at a temperature between 30 C. and 180 C.

7. Process according to claim 1, wherein at least one least one saturated fatty acid with a 16-22 carbon chain chosen from the groups consisting of stearic acid, palmitic acid, arachidic acid and behenic acid is used in step (1).

8. Process according to claim 1, wherein the reaction of step (2) is a hydrogenation.

9. Process according to claim 8, wherein the hydrogenation is carried out with H.sub.2-gas.

10. Process according to claim 8, wherein the hydrogenation is a transfer hydrogenation.

11. Process according to claim 10, wherein the transfer hydrogenation is a transfer hydrogenation is carried out in the presence of at least one metal-complex, wherein the metal is chosen from the group consisting of Ir, Rh and Ru.

12. Process according to claim 11, wherein the metal-complex is chosen from the group consisting of pentamethylcyclopentadienyl Ir-complex (Cp*Ir), Cp*Rh, Ru-arene-complexes, preferably Ru-p-cymene and Ru-benzene complexes.

13. Process according to claim 11, wherein the metal-complex also comprises at least one organic ligand, which comprises at least one N and/or P atom.

14. Process according to claim 13, wherein the organic ligand are 1,2 amino alcohols and/or mono-sulfonated 1,2-diamines.

15. Process according to claim 10, wherein the transfer hydrogenation is carried out in the presence of at least one alcohol (or a salt thereof), formic acid (or a salt thereof) or a formic acid/trimethylamine complex.

Description

EXAMPLES

Example 1

[0075] E,Z-dehydronerolidol to (2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesol (step (1)) 36.6 g (0.163 Mol) of E,Z-dehydronerolidol, and 465 mg (1.63 mMol) of stearic acid, and 5.90 g (0.212 Mol) of triphenylsilanol, and 2.95 g (3.26 mMol) of tris-(triphenylsiloxy)-vanadium oxide and 163 g of vacuum pump oil were weighed into the 350 ml four-necked flask.

[0076] The reaction mixture was heated up to 140 C. under a slight argon overflow.

[0077] The reaction mixture was stirred for five hours. Afterwards the reaction mixture was cooled down to room temperature and the product ((2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesal) was obtained by distillation in a yield of 82.6%. The amount of the 4 ((2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesal isomers were (32 wt-%, 24 wt-%, 25 wt-%, 19 wt-%).

Example 2

[0078] The same reaction as in Example 1 was carried out but instead of vacuum pump oil xylenes was used as a solvent.

[0079] The yield ((2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesal was 82.2%. The amount of the 4 ((2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesal isomers were (34 wt-%, 24 wt-%, 25 wt-%, 17 wt-%)

Example 3

[0080] The same reaction as in Example 1 was carried out, but without stearic acid.

[0081] The yield ((2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesal was 79.9%. The amount of the 4 ((2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesal isomers were (29 wt-%, 19 wt-%, 31 wt-%, 21 wt-%)

Example 4

[0082] E-dehydronerolidol to (2E/6E, 2Z/6E)-farnesol

[0083] The same reaction as in Example 1 was carried out, but E-dehydronerolidol was used as starting material.

[0084] The yield (2E/6E, 2Z/6E)-farnesal was 89.2%. The amount of the 2 (2E/6E, 2Z/6E)-farnesal isomers were (52 wt-%, 48 wt-%)

Example 5

[0085] (2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesal to (2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesol (step (2))

[0086] In a 25 ml round bottomed flask with magnetic stirrer and argon overlay 12.3 mg (0.02 mMol) of dichloro(p-cymene)ruthenium(II) dimer and 9.5 mg (0.044 mMol) of N-(2-aminoethyl)-4-methylbenzenesulfonamide were solved in 9 ml (8.05 g; 91 mMol) of ethyl acetate under stirring for 30 minutes at room temperature.

[0087] Afterwards 1.74 g (20 mMol) of formic acid triethylamine complex 5:2 and then 1.07 g (4.9 mMol) of farnesal (2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesal) (obtained from example 1) were weighed in. The solution was stirred for 20 hours at RT.

[0088] (2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesol was obtained in yield of 98%. The amount of the 4 (2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesal isomers were (28 wt-%, 25 wt-%, 25 wt-%, 22 wt-%)

Example 6

[0089] (2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesal to (2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesol (step (2))

[0090] In a 250 ml flask with magnetic stirrer and argon overlay 8.75 g (32.6 mMol) of farnesal ((2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesal) (obtained by example 1) and 6.66 mg (23.6 mMol) of triisopropoxyaluminum were solved in 20.5 g (342 mMol) of isopropanol. The reaction mixture was stirred under reflux at a temperature of 98 C. for 19 h.

[0091] Afterwards (2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesol was obtained by extraction at yield of 81.4%. The amount of the 4 (2E/6E, 2Z/6E, 2E/6Z, 2Z/6Z)-farnesal isomers were (29 wt-%, 25 wt-%, 25 wt-%, 21 wt-%)

Example 7

[0092] (2E/6E, 2Z/6E)-farnesal to (2E/6E, 2Z/6E)-farnesol (step (2))

[0093] The same reaction as in Example 5 was carried out, but (2E/6E, 2Z/6E)-farnesal from Example 4 was used as starting material.

[0094] The yield (2E/6E, 2Z/6E)-farnesol was 86.2%. The amount of the 2 (2E/6E, 2Z/6E)-farnesol isomers were (52 wt-%, 48 wt-