PROCESS FOR OBTAINING ENANTIOMERS OF CHRYSANTHEMIC ACID

摘要

A new process is described, easy to perform on industrial scale, with high yield, for obtaining enantiomers of chrysanthemic acid starting from mixtures containing them. The process involves reacting said mixtures with enantiomers of 2- dimethylamino-1-phenyl-1 ,3-propanediol (DMPP) and 2-dimethylamino-1-[4- (methylthio)phenyl]propane-1 ,3-diol (MTDP) as chiral selectors. The invention includes salts of chrysanthemic acid with the aforesaid chiral selectors as process intermediates. The process allows operation in a single solvent rather than in solvent mixtures difficult to recover and reuse, and the final crystallization product does not incorporate molecules of solvent. The bases used are then recovered and reused in subsequent separations.