Process of making D-panthenyl triacetate
View Patent ↗A process of making D-panthenyl triacetate which includes reacting D-panthenol with acetic anhydride in the presence of the catalyst polymer bound dimethylaminopyridine to form an exothermic mixture. The so-produced acetic acid, and the catalyst are removed from the exothermic mixture which is then neutralized with sodium hydroxide. Sodium acetate in the form of a solid is removed by filtration. The D-panthenyl triacetate is useful in cosmetic compositions.
1. A process of making D-panthenyl triacetate comprising the steps of:
a) esterifying D-panthenol in the presence of acetic anhydride and polymer bound dimethylaminopyridine which form an exothermic mixture;
b) heating the exothermic mixture for a sufficient time to complete the reaction;
c) removing the acetic acid formed in the exothermic mixture by distillation;
d) removing the polymer bound dimethylaminopyridine by filtration;
e) neutralizing the exothermic mixture with a sodium hydroxide solution to precipitate sodium acetate; and
f) removing the precipitated sodium acetate by filtration.
2. A process of making D-panthenyl triacetate comprising the steps of:
a) mixing D-panthenol, polymer bound dimethylaminopyridine and acetic anhydride to form an exothermic mixture;
b) heating the exothermic mixture to about 75° C. to 85° C. under atmospheric conditions to complete the reaction in the exothermic mixture;
c) pre-stripping the exothermic mixture at about 85° C. to 100° C. to decrease the volume of the exothermic mixture;
d) cooling the exothermic mixture to about 65° C. to 75° C.;
e) removing the polymer bound dimethylaminopyridine by filtering the exothermic mixture;
f) stripping the remaining acetic acid from the exothermic mixture by placing the exothermic mixture under vacuum of less than or equal to 25 mmHg and heating to about 95° C. to 105° C.;
g) cooling the exothermic mixture to about 45° C. to 55° C.;
h) neutralizing the exothermic mixture with a sodium hydroxide solution;
i) removing sodium acetate and excess sodium hydroxide by filtration; and
j) removing water from the exothermic mixture by stripping to obtain D-panthenyl triacetate.
3. The process of claim 2 wherein the exothermic mixture in step b) is heated to 80° C.
4. The process of claim 2 wherein the exothermic mixture in step c) is heated to 95° C.
5. The process of claim 2 wherein the exothermic mixture in step d) is cooled to 70° C. and filtered to remove the polymer bound dimethylaminopyridine.
6. The process of claim 2 wherein the exothermic mixture in step f) is placed under vacuum and heated to 105° C. to remove acetic acid.
7. The process of claim 2 wherein the exothermic mixture in step g) is cooled to 50° C. and in step h) the exothermic mixture is neutralized with an aqueous solution of sodium hydroxide.
8. A process of making D-panthenyl triacetate comprising the steps of:
a) mixing D-panthenol with polymer bound dimethylaminopyridine by stirring to obtain a mixture thereof;
b) adding acetic anhydride to the mixture and heating the mixture to about 80° C.;
c) removing acetic acid to a concentration of about 4% w/w by vacuum distillation;
d) removing the polymer bound dimethylaminopyridine by filtration;
e) neutralizing the mixture with an aqueous sodium hydroxide solution and precipitating sodium acetate therein;
f) removing the solid sodium acetate by filtration; and
g) removing residual water from the solution under vacuum to obtain D-panthenyl triacetate.