Synthesis of new 5-oxazolones: Their ring opening reactions to obtain new benzamide derivatives

New 5-oxazolones have been synthesized via N-protected amino acids which were prepared from various aryl acyl halides and L-amino acids, with DCC. Then, we studied the ring opening reactions of 5-oxazolones with nucleophilic attack by primary aryl amines to obtain new racemic benzamide derivatives. All new synthesized compounds have been characterized by FTIR, ¹H, ¹³C NMR, GC/MS, LC/MS and Qtof analyses. X-Ray results of N-(1-((4-chlorophenyl)amino)-3-methyl-1-oxopentan-2-yl)-3-(trifluoromethyl)benzamide clearly showed absolute stereostructure.