PROCESS FOR PREPARING 3-METHYLCYCLOPENTADECANE-1,5-DIONE

Abstract

The present invention relates to a process for producing 3-methylcyclopentadecane-1,5-dione of formula (I), which comprises the oxidation of 14-methyl-bicyclo[10.3.0]pentadecen[1 (12)] of formula (II) with an oxidizing agent, where the oxidation is performed by using a mixture of formic acid with H.sub.2O.sub.2 as sole oxidizing agent in the presence of water and where the amount of H.sub.2O.sub.2 is at least 1.1 mol H.sub.2O.sub.2 per mol of the compound of formula (II).

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Claims

1.-11. (canceled)

12. A process for preparing 3-methylcyclopentadecane-1,5-dione, which comprises oxidizing 14-methylbicyclo[10.3.0]pentadecen[1(12)] with an oxidizing agent, where the oxidation is performed by using a mixture of formic acid with H.sub.2O.sub.2 as sole oxidizing agent in the presence of water and where the amount of H.sub.2O.sub.2 is at least 1.1 mol H.sub.2O.sub.2 per mol of 14-methylbicyclo[10.3.0]pentadecen[1(12)].

13. The process of claim 12, wherein the amount of H.sub.2O.sub.2 is from 1.4 to 4.0 mol H.sub.2O.sub.2 per mol of 14-methylbicyclo[10.3.0]pentadecen[1(12)].

14. The process of claim 12, wherein the amount of H.sub.2O.sub.2 is from 15 to 3.5 mol H.sub.2O.sub.2 per mol of 14-methylbicyclo[10.3.0]pentadecen[1(12)].

15. The process of claim 12, wherein H.sub.2O.sub.2 is added to the mixture of 14-methylbicyclo[10.3.0]pentadecen[1(12)] and formic acid.

16. The process of claim 14, wherein the total amount of added H.sub.2O.sub.2 is added over a period of at least 2 h.

17. The process of claim 14, wherein the total amount of added H.sub.2O.sub.2 is added over a period of from 2 to 24 h.

18. The process of claim 14, wherein less than 70% of the total amount of H.sub.2O.sub.2 used in the process is present at the beginning of the oxidation.

19. The process of claim 14, wherein less than 70% and at most 50% of the total amount of H.sub.2O.sub.2 used in the process is present at the beginning of the oxidation

20. The process of claim 16, wherein at least 50% of the total amount of H.sub.2O.sub.2 are added to the reaction mixture while the oxidation reaction takes place.

21. The process of claim 12, wherein the oxidation of the compound of 14-methylbicyclo[10.3.0]pentadecen[1(12)] is performed at a temperature of 20 to 100 C.

22. The process of claim 12, wherein the oxidation of the compound of 14-methylbicyclo[10.3.0]pentadecen[1(12)] is performed at a temperature of from 0 to 80 C.

23. The process of claim 12, wherein the oxidation of the compound of 14-methylbicyclo[10.3.0]pentadecen[1(12)] is performed at a temperature of from 10 to 60 C.

24. The process of claim 12, wherein the concentration of water in the reaction mixture is from 3 to 25% by weight.

25. The process of claim 12, wherein H.sub.2O.sub.2 is used as an aqueous solution.

26. The process of claim 25, wherein the concentration of H.sub.2O.sub.2 in the aqueous H.sub.2O.sub.2 is from 25 to 50% by weight.

27. The process of claim 12, where the weight ratio of 14-methylbicyclo[10.3.0]pentadecen[1(12)] and the formic acid is in the range from 1:20 to 1:2.

Description

EXAMPLES

[0024] I) Gas Chromatographic Analysis:

[0025] GC-system and separation method:

[0026] GC-system: Agilent 7890 Series A;

[0027] GC-Column: DB-WAX (30 m (Length), 0.32 mm (ID), 0.25 m (Film));

[0028] Injector at 230 C., detector at 280 C. and flow 1.5 mL.

[0029] Temperature program: 80 C. to 250 C. in 3 C./min, 250 C. for 15 min.

[0030] II) Production Examples:

Comparative Example 1

According to CH 513791

[0031] 2.5 g (0.01 mol) of 14-methylbicyclo[10.3.0]pentadecen[1(12)] were dissolved at 22 C. in 30 mL of concentrated formic acid (90%). The mixture was heated to 40 C. At this temperature 0.55 g of 50% (w/w) aqueous H.sub.2O.sub.2 (8 mmol, 0.8 eq.) were added drop wise. After having completed the addition, the reaction mixture was stirred at 40 C. for 6 h. Then, the reaction mixture was cooled down to 22 C. and left standing overnight. Then 15 mL of a 10% (w/w) aqueous Na.sub.2SO.sub.3 solution were slowly added and the reaction mixture was stirred at 22 C. for 1 h. Then, the reaction mixture was evaporated at reduced pressured and 15 mL of ethanol were added to the residue followed by 40 mL of a 10% (w/w) aqueous KOH solution. The mixture was stirred for 4 h at 22 C. and the product was extracted with ethyl acetate. The organic phase was washed with water and the solvent was evaporated in the rotavapor to obtain 2 g of a crude product which contained 82% (GC area) of 14-methylbicyclo[10.3.0]pentadecen[1(12)] and a 3% (GC area %) of 3-methylcyclopentadecane-1,5-dione.

Comparative Example 2

According to CH 513791 but with 35% H.SUB.2.O.SUB.2

[0032] 2.5 g (0.01 mol) of 14-methylbicyclo[10.3.0]pentadecen[1(12)] were dissolved at 22 C. in 30 mL of concentrated formic acid (90%). The mixture was heated to 40 C. At this temperature 0.8 g of 35% (w/w) aqueous H.sub.2O.sub.2 (0.8 eq.) were added dropwise. After having completed the addition, the reaction mixture was stirred at 40 C. for 6 h. Then, the reaction mixture was cooled down to 22 C. and left standing overnight. Then 15 mL of a 10% (w/w) aqueous Na.sub.2SO.sub.3 solution were slowly added and the reaction mixture was stirred at 22 C. for 1 h. Then, the reaction mixture was evaporated at reduced pressured and 15 mL of ethanol were added to the residue followed by 40 mL of a 10% (w/w) aqueous KOH solution. The mixture was stirred for 4 h at 22 C. and the product was extracted with ethyl acetate. The organic phase was washed with water and the solvent was evaporated in the rotavapor to obtain 2 g of a crude product which contained 76% (GC area) of 14-methylbicyclo[10.3.0]pentadecen[1(12)] and a 8% (GC area %) of 3-methylcyclopentadecane-1,5-dione.

Example 1

3.2 eq. of H.SUB.2.O.SUB.2

[0033] 2.5 g (0.01 mol) of 14-methylbicyclo[10.3.0]pentadecen[1(12)] were dissolved at 22 C. in 30 mL of concentrated formic acid (90%). The mixture was heated to 40 C. At this temperature 3.1 g of 35% (w/w) aqueous H.sub.2O.sub.2 (32 mmol, 3.2 eq.) were added dropwise. After having completed the addition, the reaction mixture was stirred at 40 C. for 3 h. Then, the reaction mixture was cooled down to 22 C. and 30 mL of a 10% (w/w) aqueous Na.sub.2SO.sub.3 solution were slowly added. Then, the reaction mixture was extracted with dichloromethane. The organic phase was collected and after a negative test for peroxide the organic solvents were evaporated in a rotavap. The obtained oil was re-dissolved in ethyl acetate and the solution was washed with a 10% (w/w) aqueous KOH solution and with water. The organic phase was dried with Na.sub.2SO.sub.4 and the solvent was evaporated under reduced pressure to obtain 2.1 g of a crude product which contained 43% (GC area %) of 3-methylcyclopentadecane-1,5-dione, representing a yield of 36%, based on 14-methylbicyclo[10.3.0]pentadecen[1(12)].

Example 2

3.2 eq. of H.SUB.2.O.SUB.2., Large Scale

[0034] 70 g (0.317 mol) of 14-methylbicyclo[10.3.0]pentadecen[1(12)] were dissolved at 22 C. in 300 mL of concentrated formic acid (90%). The mixture was heated to 40 C. At this temperature 115 mL of 30% (w/w) aqueous H.sub.2O.sub.2 (1.014 mmol, 3.2 eq.) were added drop wise. After having completed the addition, the reaction mixture was stirred at 40 C. for 3 h. Then, the reaction mixture was cooled down to 22 C. and 300 mL of a 20% (w/w) aqueous Na.sub.2SO.sub.3 solution were slowly added. Then, the reaction mixture was extracted with dichloromethane. The organic phase was collected and after a negative test for peroxide the organic solvents were evaporated in a rotavap. The obtained oil was re-dissolved in ethyl acetate and the solution was washed with a 10% (w/w) aqueous KOH solution and with water. The organic phase was dried with Na.sub.2SO.sub.4 and the solvent was evaporated under reduced pressure to obtain 80.1 g of a crude product which contained 23% (GC weight %) of 3-methylcyclopentadecane-1,5-dione, representing a yield of 25%, based on 14-methylbicyclo[10.3.0]pentadecen[1(12)].

Example 3

H.SUB.2.O.SUB.2 .Dosing

[0035] 5 g (0.02 mol) of 14-methylbicyclo[10.3.0]pentadecen[1(12)] were dissolved at 22 C. in 30 mL of concentrated formic acid (90%). The mixture was heated to 40 C. At this temperature 1.8 g of 30% (w/w) aqueous H.sub.2O.sub.2 (0.016 mmol, 0.8 eq.) were added drop wise. After having completed the addition, the reaction mixture was stirred at 40 C. for 3 h. Then, a sample was taken andafter work-up as described for example 1the sample was analyzed by GC. Then, further 1.8 g of 30% (w/w) aqueous H.sub.2O.sub.2 were added and the mixture was stirred for 3 additional hours at 40 C. This procedure was repeated two times. After each reaction period of 3 h, samples were taken and analyzed by GC after work-up. Then the reaction mixture was cooled down to 22 C. and 30 mL of a 10% (w/w) aqueous Na.sub.2SO.sub.3 solution were slowly added. Then, the reaction mixture was extracted with ethyl acetate. The organic phase was washed with saturated aqueous NaHCO.sub.3 and water. The organic extracts were collected, dried with Na.sub.2SO.sub.4 and the solvent was evaporated under reduced pressure. By stopping the reaction after the addition of 1.6 eq of H.sub.2O.sub.2 (20.8 eq) a maximum selectivity of 77% for 3-methylcyclopentadecane-1,5-dione could be obtained.

TABLE-US-00001 Conver- Dike- Selec- Sample sion(%)* tone (%) tivity(%)** 3 h (0.8 eq H.sub.2O.sub.2).sup. 14% 9.5% 70% 6 h (2 0.8 eq H.sub.2O.sub.2) 65% 50% 77% 9 h (3 0.8 eq H.sub.2O.sub.2) 82% 54% 66% 12 h (4 0.8 eq H.sub.2O.sub.2) 100% 55% 55% *Based on 14-methylbicyclo[10.3.0]pentadecen[1(12)] GC area %. **Based on 3-methylcyclopentadecane-1,5-dione GC area %.