Use of an Iodide-Modified Merrifield Resin in the Synthesis of Ruthenium Hydride Complexes. The Structure of RuHI((R)-binap)(PPh3)

Abstract

Transition metal complexes that function as catalysts or precatalysts are sometimes synthesized by the displacement of phosphine ligands from precursor complexes. A common problem in the synthesis is the separation of the desired complex from the phosphine contaminants that have similar solubility properties. This is the case in the synthesis of the coordinatively unsaturated ruthenium complexes RuHX((R)-binap)(PPh3) (X = Cl, 2; X = I, 3) from RuHCl(PPh3)3 (1). The new iodo ruthenium complex RuHI((R)-binap)(PPh3) (3) is prepared in good yield and purity by treatment of the chloro derivative 2, which is contaminated with triphenylphosphine, triphenylphosphine oxide, binap, binap monoxide, and binap dioxide, with an iodide-modified Merrifield resin. The resin was prepared following a modification of a procedure described by Lipshutz and Blomgren. The structure determination of 3 by single-crystal X-ray diffraction is reported. Complex 3 reacts with the alkoxides KOCR2-2-py (R = Me, potassium dimethyl-2-pyri...