MOP-phosphonites: A novel ligand class for asymmetric catalysis

Abstract

Chiral phosphonite ligands (S,R b)-5a, (S,S b)-5b, (R,R b)-6a and (R,S b)-6b are introduced, comprising a MOP-type backbone with a binol-based binaphthyl group bound to the phosphorus. Their reaction with [Pd(η 3-C 4H 7)Cl] 2 affords η 3-methallylpalladium chloride complexes 7a/b and 8a/b which have been isolated and structurally characterised. Solid-state and solution studies indicate subtle differences in their coordination behaviour, which ultimately affects their efficacy in the asymmetric hydrosilylation of styrene. © The Royal Society of Chemistry 2012.