Synthesis of spiropyrrolidines and spiropyrrolizidines by 1,3-dipolar cycloadditions of azomethine ylides to substituted α-methylene-γ-lactones
作者:Jakub Častulı́k、Jaromı́r Marek、Ctibor Mazal
DOI:10.1016/s0040-4020(01)00807-9
日期:2001.9
1,3-Dipolar cycloadditions of (E)- and (Z)-substituted α-methylene-γ-lactones with azomethine ylides derived from N-methyl glycine and l-proline gave the corresponding spiropyrrolidine and spiropyrrolizidine cycloadducts in good to moderate yields with various extent of stereoselectivity and regioselectivity. Cycloadditions of the azomethine ylide derived from l-proline exhibited endo selectivity especially