Potassium Cyanide → HCID 23297209, compound

Participants

Reaction Steps

Advantageously, compared to this preparation which comprises six steps in all, the preferred process for the purposes of the invention, which is faster and more economical, enables (S)-(-)-2-amino-2-(3,4-dichlorobenzyl)-1-propanol to be prepared in four synthesis steps from 3,4-dichlorophenylacetone. Essentially, the process consists in reacting the ketone by the Bucherer-Berg reaction with potassium cyanide and ammonium carbonate to obtain (+/-)-5-(3,4-dichlorobenzyl)-5-methylhydantoin, which is subjected in an alkaline aqueous-acetone medium to a stereospecific salification with (R)-(+)-α-methylbenzylamine so as to obtain the addition salt thereof with the (S)-(-) enantiomer of the hydantoin, which, being insoluble, is filtered off, and from which (S)-(-)-5-(3,4-dichlorobenzyl)-5-methylhydantoin is obtained in a state of optical purity greater than 98% by treatment in an acid solution.

Provenance & Evidence