Processes for preparing solid tocopherol succinate calcium and magnesium salts
Processes for preparing salts of alcohol polybasic acid partial esters are described wherein an alcohol polybasic acid partial ester is reacted with a compound selected from the group consisting of metal oxides, metal hydroxides, metal carbonates and mixtures thereof.
1. A process for preparing d-α-tocopherol calcium succinate, the process comprising:
(a) providing d-α-tocopherol succinate; and
(b) reacting the d-α-tocopherol succinate with an equivalent excess of a metal compound selected from the group consisting of calcium oxide and calcium hydroxide at a temperature of from 50 to 70° C. in a liquid solvent comprising a monohydric C1–4 alcohol with or without water as a co-solvent.
2. The process according to claim 1 , wherein the liquid solvent is methanol without water as a co-solvent.
3. The process according to claim 1 , wherein the liquid solvent is methanol which contains less than 0.5% water.
4. The process according to claim 1 , wherein the metal compound is reacted with tocopherol succinate or mixture of tocopherol succinates in an equivalent ratio of 1.1:1 or greater.
5. A process for preparing a tocopherol metal succinate, the process comprising:
(a) providing a tocopherol succinate or a mixture of tocopherol succinates; and
(b) reacting the tocopherol succinate or a mixture of tocopherol succinates with an equivalent excess of a metal compound selected from the group consisting of calcium oxide, calcium hydroxide, calcium carbonate, magnesium oxide, magnesium hydroxide and zinc oxide at a temperature of from 50 to 70° C. in a liquid solvent comprising a monohydric C1–4 alcohol with or without water as a co-solvent.
6. The process according to claim 5 , wherein the tocopherol is selected from alpha (α-), beta (β-), gamma (γ-) and delta (δ-) homologues of tocopherol, tocomonoenols, tocodienols and tocotrienols and mixtures thereof.
7. The process according to claim 5 , wherein the tocopherol is a naturally derived tocopherol.
8. The process according to claim 5 , wherein the tocopherol is d-α-tocopherol.
9. The process according to claim 5 , wherein the metal compound is calcium oxide or calcium hydroxide.
10. The process according to claim 5 , wherein the liquid solvent is methanol without water as a co-solvent.
11. The process according to claim 5 , wherein the liquid solvent is methanol which contains less than 0.5% water.
12. The process according to claim 5 , wherein the metal compound is reacted with the tocopherol succinate or mixture of tocopherol succinates in an equivalent ratio 1.05:1 or greater.
13. The process according to claim 7 , wherein the metal compound is calcium oxide or calcium hydroxide and is reacted with the naturally derived tocopherol succinate in an equivalent ratio of 1.1:1 or greater.
14. The process according to claim 13 , further comprising recovering the solid d-α-tocopherol calcium succinate product of step (b) by filtration.
15. The process according to claim 5 , further comprising recovering the solid tocopherol metal succinate product of step (b) by filtration.
16. A process for preparing solid d-α-tocopherol calcium succinate, the process comprising:
(a) providing d-α-tocopherol succinate; and
(b) reacting the d-α-tocopherol succinate with an equivalent excess of a metal compound selected from the group consisting of calcium hydroxide at a temperature of from 50 to 70° C. in a liquid solvent comprising methanol, and
(c) filtering the reaction mixture to recover the solid d-α-tocopherol calcium succinate.
17. The process according to claim 16 , wherein the methanol contains less than 0.5% water.
18. The process according to claim 16 , wherein the metal compound is reacted with the tocopherol succinate or mixture of tocopherol succinate in an equivalent ratio of 1.1:1 or greater.