PROCESS FOR THE PREPARATION OF PYRROLIDONE DERIVATIVES

摘要

Process for preparing pyrrolidinone derivatives of (1) (1) in which R is hydrogen, alkyl or acyl characterized in that a compound of (2) (2) wherein R1 is hydrogen and R2 is benzyl or substituted benzyl, or R1 and R2 can together form a group where R4 and R5 are independently hydrogen, alkyl, phenyl or optionally substituted aryl or together are 1,4-butylene or 1,5-pentylene; R3 is hydrogen or straight or branched alkyl of 1 to 4 carbon atoms; and X is alkyl subjected to N-deprotection and the deprotected intermediate is cyclized intramolecularly. The deprotected intermediates can be isolated as acid-addition salts.