Abstract Amidoalkylation of 1, 3-dienes with the adduct of glyoxylic acid-methyl carbamate (1) afforded α-acylamino-γ-alkenyl-γ-butyrolactones (eg 2, 6-9) in 40–80% yield and the pipecolic acid derivatives (eg 3) in less than 20% yield. An explanation is suggested to account for above results.