A one-pot synthesis of β-lactams (4) was successfully achieved by the reaction of β-haloacyl chlorides (1) with α-amino acids (2) in aqueous 5% sodium hydroxide solution in the absence of phase transfer catalyst in yields of 43-91%.
Inter- and intra-molecular N-alkylation of α-halocarboxamides and dihalocarboxamides in the presence of solid phase transfer catalyst led to the corresponding piperazine-2,5-diones (2) and lactams (4) in the yields of 64–88 and 63–99%, respectively. A one-pot synthesis of β-lactams (7) from α-methyl-α,β-dibromopropionyl chloride (5) and α-amino acid using phase transfer catalyst was also successfully achieved.