Template-induced enantioselectivity in the reductive radical cyclization of 3-(3-iodopropoxy)propenoic acid derivatives depending on the binding motif

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.