Enantiodivergent synthesis of 1,2-bis(diphenylphosphino)ethanes via asymmetric [3 + 2]-cycloaddition

Abstract

The present work provides efficient access to chiral cyclic 1,2-bis(diphenylphosphino)ethanes (DPPEs) directly from diphosphine oxide alkenes and azomethine ylides via asymmetric [3 + 2] cycloaddition. Both enantiomers of the products can be obtained in good to excellent diastereo- and enantioselectivities (up to >20 : 1 dr and 99% ee). Mild conditions, gram-scale experiment, diverse transformations and preliminary catalytic applications of the DPPEs make this approach highly attractive.