Chiral diiminophosphoranes: a new class of ligands for enantioselective transition metal catalysis

Abstract

Chiral diamines such as (1R,2R)-1,2-diaminocyclohexane or R-2,2′-diamino-1,1′-binaphthalene can be converted into the corresponding diimino(triphenyl)phosphoranes, which serve as C₂-symmetric ligands for enantioselective transition metal catalyzed reactions such as copper-mediated cyclopropanations.

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