Chemoselective asymmetric dearomative [3 + 2] cycloaddition reactions of purines with aminocyclopropanes

Abstract

Chemoselective asymmetric [3 + 2] cycloaddition reactions of purines with aminocyclopropanes for the dearomatization of purines have been successfully developed. In the presence of a copper complex, derived from Cu(OTf)₂ and bisoxazoline, a series of hydropyrrolo-purine compounds were obtained in high yields (up to 98%) with excellent enantioselectivities (up to 99% ee). The chemoselectivity in current cycloaddition reactions has been explained by density functional theory calculations.