Claims
- 1. A process for producing .alpha.-tocopherol from a non-.alpha.-tocopherol, wherein the non-.alpha.-tocopherol is free of or admixed with .alpha.-tocopherol, which process comprises reacting the non-.alpha.-tocopherol with formaldehyde or formaldehyde-producing compound in a reaction mixture which further comprises boric acid or a boric acid-producing compound and a solvent comprising an azeotropic mixture of trimethyl borate and methanol and a non-polar organic solvent wherein:
- said reaction is carried out under catalytic reducing conditions at a temperature in the range from about 130.degree. C. to about 180.degree. C.; and
- the mol equivalent ratio of formaldehyde to non-.alpha.-tocopherol is in a range from about 2:1 to about 10:1, the mol equivalent ratio of boric acid to total non-.alpha.-tocopherol and .alpha.-tocopherol is in a range from about 0.1:1 to about 4:1, the mol equivalent ratio of trimethyl borate to total non-.alpha.-tocopherol and .alpha.-tocopherol is in a range from about 0.1:1 to about 10:1, and the ratio of liters of non-polar organic solvent per mol equivalent of total non-.alpha.-tocopherol and .alpha.-tocopherol is in a range from about 1:1 to about 10:1;
- so that the non-.alpha.-tocopherol is reacted to produce the .alpha.-tocopherol.
- 2. The process of claim 1 wherein the catalytic reducing conditions comprises reacting the non-.alpha.-tocopherol and the formaldehyde or formaldehyde-producing compound in the presence of sufficient quantity of a noble metal hydrogenation catalyst and under sufficient hydrogen pressure so that the non-.alpha.-tocopherol is reacted to produce the .alpha.-tocopherol.
- 3. The process of claim 2 wherein the boric acid-producing compound is trimethyl borate and the reaction mixture further comprises water wherein the mol equivalent ratio of water to total non-.alpha.-tocopherol and .alpha.-tocopherol is in the range from about 0.3:1 to about 12:1.
- 4. The process of claim 3 wherein the weight ratio of trimethyl borate to methanol in the azeotropic mixture in is a range from about 50:50 to about 75:25.
- 5. The process of claim 4 wherein the mol equivalent ratio of trimethyl borate to total non-.alpha.-tocopherol and .alpha.-tocopherol is in a range from about 1:1 to about 4:1.
- 6. The process of claim 5 wherein the non-polar organic solvent is a lower alkane, a mixture of lower alkanes or an aromatic hydrocarbon.
- 7. The process of claim 6 wherein the mol ratio of formaldehyde to non-.alpha.-tocopherol is in a range from about 4:1 to about 8:1.
- 8. The process of claim 7 wherein the non-polar organic solvent is n-hexane.
- 9. The process of claim 8 wherein the reaction is carried out at a temperature in a range from about 140.degree. C. to about 170.degree. C.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2951/95 |
Oct 1995 |
CHX |
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Parent Case Info
This is a continuation of application Ser. No. 08/729,967, filed Oct. 15, 1996, now abandoned.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
3338922 |
Kijima et al. |
Aug 1967 |
|
3819657 |
Baldwin et al. |
Jun 1974 |
|
Foreign Referenced Citations (3)
Number |
Date |
Country |
178 400 |
Apr 1986 |
EPX |
191 132 |
Aug 1986 |
EPX |
60-4183 |
Feb 1985 |
JPX |
Continuations (1)
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Number |
Date |
Country |
Parent |
729967 |
Oct 1996 |
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