The first enantiomerically pure synthesis of (2S,1′S)-(cyclopent-2-enyl)glycine by boron trifluoride mediated asymmetric 1,3-diploar cycloaddition

Abstract

Chiral spiro nitrone 3, treated with (3-trimethylsilyl)cyclopent-1-ene in the presence of BF₃.Et₂O, gives the 1,3-diploar cycloadduct 4 as a single isomer, which converted to (2S,1′S)-(cyclopent-2-enyl)glycine (2S,1′S)-7 by alkaline hydrolysis, catalytic reduction and BF₃ mediated alkene formation.