Modulation of the coordination geometries of NCN and NCNC Rh complexes for ambidextrous chiral catalysts.

A chirality switch between novel NCN pincer Rh complexes and a related double cyclometalated NCNC Rh complex containing secondary amino groups is described. Their catalytic abilities were determined in asymmetric alkynylation of ethyl trifluoropyruvate, and the change in the coordination geometry of the Rh catalysts affected the stereochemistry of the products.