The enantioselective Kinugasareaction of nitrones with terminal alkynes in the presence of 20 mol % of IndaBox–Cu(OTf)2 and di-sec-butylamine (1.5 equiv) produced β-lactams with the highest level of enantiomeric excesses among the catalytic enantioselective Kinugasareactions reported so far.
Chiral tris(oxazoline)/Cu(I) complexes are demonstrated as a type of efficient catalysts for the asymmetric Kinugasa reaction of terminal alkynes with C-arylnitrones, providing a highly enantio- and diastereoselective access to optically active beta-lactams. (C) 2012 Elsevier Ltd. All rights reserved.