Convenient Syntheses of Cyclic Carboxamides from α, β, γ, δ and ε-Halocarboxamides under Phase Transfer Conditions

Abstract

Piperazine-2, 5-diones (2) were prepared by N-alkylation between two molecules of α-halocarboxamides (1) in the presence of a phase transfer catalyst in yields of 64-88%. β, γ, δ and ε-Lactams (6, 9 and 13) were similarly synthesized by intramolecular N-alkylation of the corresponding halocarboxamides (5, 8 and 12) under phase transfer conditions in 53-99% yields.