Process for the preparation of 2-(1-hydroxyalkyl)-5,5-diphenylhydantoin

摘要

Described is a process for preparing 2-(1-hydroxyalkyl)-5,5-diphenylhydantoin having the formula <IMAGE> wherein R1, R2 and R3 are each independently hydrogen, C1-C20 alkyl, C3-C12 cycloalkyl, C7-C15 aralkyl, unsubstituted or substituted aryl or heteroaryl or alternatively, or R1 and R2 together with the carbon atom form a 3 to 12 member cycloalkyl group, the process comprising: reacting diphenylhydantoin with an aldehyde or a ketone in the presence of a strong inorganic base; an alcohol was used as solvent to solubilize the reactants. The reaction is practically complete in 15 minutes. The compounds so prepared are intermediates in the preparation of phenyltoin prodrugs.