2,3-Dihydroxybutanedioic Acid → Ritanserin

Participants

Reaction Steps

A mixture of 4 parts of 6-[2-[4-[bis(4-fluorophenyl)-methylene]-1-piperidinyl]ethyl]-7-methyl-5H-thiazolo[3,2-a]-pyrimidin-5-one, 1.3 parts of (+)-[R-(R*,R*)]-2,3-dihydroxybutanedioic acid and 96 parts of 2-propanol was stirred and heated till all solid entered solution. The whole was cooled while stirring. The product was filtered off and dried, yielding 5.1 parts (98%) of (+)-6-[2-[4-[bis(4-fluorophenyl)methylene]-1-piperidinyl]ethyl]-7-methyl-5H-thiazolo[3,2-a]pyrimidin-5-one [R-(R*,R*)]-2,3-dihydroxybutanedioate(1:1).; mp. 198.7° C. (compound 147).

Provenance & Evidence