Thermal hetero [3 + 2] cycloaddition of dipolar trimethylenemethane to N-sulfonyl and N-acyl imines. Synthesis of γ-amino acid derivatives

Article abstract of DOI:10.1246/cl.1999.879

Thermal hetero [3 + 2] cycloaddition reaction of a dipolar trimethylenemethane 2 with an N-acyl or N-tosyl imine gives an α-methylene-γ-pyrrolidone acetal 4 in high yield, which upon hydrolysis affords a γ-amino acid derivative.