Preconversion catalytic deoxygenation of phenolic functional groups. July 1 - September 30, 1996

Most industrial processes require the use hydrocarbon based solvents that have been shown to hurt the environment. Chlorine radicals from chlorine based hydrocarbons are considered to be a major factor in the depletion of the stratospheric ozone levels. Because of the health and environmental problems these solvents cause, there is renewed interest in water soluble organometallic complexes that can be used as catalysts in the industrially important reactions. Recently, the investigators completed an extensive study on the synthesis, characterization, and reactivity of a series of nickel trimers bridged by bis(diphenylphosphino)methane (dppm) ligands. They were able to synthesize the nickel trimers by two routes. The first route involves the synthesis of a nickel dimer Ni(CNCH{sub 3}){sub 3}({mu}CNCH{sub 3}) This dimer is then reacted with NiI{sub 2}, or CH{sub 2}I{sub 2}, to form a trimer with capping isocyanide and two terminal isocyanides, and then the terminal isocyanides are replaced with a third dppm (Scheme 1). The second procedure for the synthesis is the conproportionation of 2 equivalents of Ni(COD)2 (COD=1,5-cyclooctadiene) with 1 equivalent of NiI{sub 2} in the presence of dppm