A facile synthesis and some new reactions of N-benzylcarboxamides with essential amino acids

N-Benzyl-p-chloro and N-benzyl-2, 4-dichlorobenzamide react with chlorosulfonic acid to give the corresponding p-sulfonyl chlorides 1, 19, which on condensation with nucleophiles give amino acid derivatives 2-7 and 20-25. Some of the corresponding methyl esters 8-11 are also prepared. Hydrazinolysis of these methyl esters yield the hydrazides 12-15. Coupling reactions of some amino acid derivatives with amino acid methyl ester hydrochloride in THF-Et3N medium using the dicyclohexylcarbodiimide method famishes the desired dipeptide methyl esters 16-18, 26-28. The spectral data are briefly discussed.