Protein-conjugated iron complexes for catalyzing asymmetric carbene insertions into S-H and Si-H bonds

Abstract

Demonstrated herein are two conceptually different approaches for enantioselective activation of S-H and Si-H bonds, by using protein-conjugated iron complexes for catalyzing the reactions of carbenoids with either racemic thiol or non-chiral silane to form enantiomerically enriched products. Catalysts examined were native myoglobin and transferrin and the spontaneously formed conjugates of serum albumins with properly designed iron(III) corroles. Reactions proceed very fast in all cases and lead to products with significant enantiomeric enrichment for some of them. This extremely simple bio-catalytic approach is very useful for creating new S-C and Si-C bonds in aqueous media and may serve as the starting point for the directed evolution of artificial enzymes for such purposes.