Transition Metal Catalysis of Hydrogen Shuttling in Coal Liquefaction. Quarterly Technical Progress Report, September 1, 1985-November 30, 1985

摘要

The ultimate objective of this research is to uncover new catalytic processes for the liquefaction of coal and for upgrading coal-derived fuels by removing undesirable organosulfur, organonitrogen and organooxygen constituents. Basic to both the liquefaction of coal and the purification of coal liquids is the transfer of hydrogen from such sources as dihydrogen, metal hydrides or partially reduced aromatic hydrocarbons to the extensive aromatic rings in coal itself or to aromatic sulfides, amines and ethers. Accordingly, this study is exploring how such crucial hydrogen-transfer processes might be catalyzed by soluble, low-valent transition metal complexes under moderate conditions of temperature and pressure. During the fifth quarter of this three-year grant the following phases of this study received particular attention: (a) the principal investigator completed his three-month period as visiting scientist at Cornell University, October 1 to December 31, 1985, with Professor Roald Hoffmann on the topic of Extended Hueckel Molecular Orbital calculations of organometallic structure; (b) final gas evolution studies between LiAlH sub 4 and bipyridyl(1,5-cyclooctadiene) nickel have been made and the related manuscript written for publication; (c) gas evolution studies between diisobutylaluminum hydride and phosphine complexes of Pt(0) and Ni(0) have been undertaken, as part of our trying to understand how powerful reducing agents can be generated from such combinations; (d) hydrogen shuttling studies continue between dihydroaromatic hydrocarbons and Ni(0) complexes; (e) studies on the cleavage of benzylic C-C bonds by Ni(0) and Cr(0) complexes are being intensified; and (f) attempts are being made to isolate crystalline samples of several organonickel intermediates in the foregoing cleavage reactions, so that x-ray structure determinations can be carried out. (ERA citation 11:015515)