Asymmetric nickel-NHC catalysis

INOR 329

Rebecca M. Kissling, kissling@binghamton.edu, Catherine N. Malele, and Maurice O. Odago. Department of Chemistry, Binghamton University, P. O. Box 6000, Binghamton, NY 13902-6000
The work described is a ligand-structure-focused approach to improving both activity and selectivity in Ni-catalyzed multi-component reactions. The initial approach to experiments is guided by phenomena characterized in the recent literature: N-heterocyclic carbenes (NHCs) promote greater activity and tolerate a broader variety of conditions and substrates than phosphine ligands in similar reactions. Initial screenings utilize chiral NHCs that may be chiral in the N-alkyl side chain, the saturated backbone or, in cases, have a planar chiral element. The effect of rigidity of the N-side chain, heterocycle size, and nickel source will also be explored. The scope of the project include 1) selection of a primary set of ligand candidates; 2) determination of asymmetric induction levels in reactions promoted by achiral NHCs or phosphines, utilizing initial candidates and variants as needed; 3) comparison of stereoselection in reactions with non-racemic chiral substrates.