Enantiomerically enriched cyclopropanes and products of C–H insertion reactions were obtained in excellent combined yields and enantioselectivities as a consequence of rhodium- catalyzed decomposition of vinyl diazoacetate in the presence of tert-butoxycarbonyl-(Boc)- protected amines as trapping agents. A series of enantiomerically enriched six-to eight- membered nitrogen-containing heterocycles were subsequently prepared via ring-closing ...