Template-Induced Enantioselectivity in the Reductive Radical Cyclization of 3-(3-Iodopropoxy)propenoic Acid Derivatives Depending on the Binding Motif

Abstract

Different binding motifs HXC=O have been screened in the enantioselective radical cyclization of various linear derivatives of 3-(3-iodopropoxy)propenoic acid. The reactions were performed in the presence of an enantiomerically pure, chiral 1,5,7-trimethyl-3-azabicyclo[3.3.1]nonan-2-one derivative, which acts as a hydrogen-binding template. The cyclized products were obtained in good to excellent yields (66-88%). Enantioselectivities up to 59% ee were achieved.

Key words

cyclizations - enantioselectivity - lactams - radical reactions - supramolecular chemistry

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