'~ ( Photochemistry of Cobalt Carbonyl Complexes K(aving =It eriimjfechna1,Rl0 a Cobalt-Silicon Bond and/Zts Importance in- Activation of Catalysis 6. PERFORMING ORG. REPORT NU114911

Approved for public release; reproduction is permitted for ahy purpose of the United States Government; distribution unlimited DI 17. DISTRIBUTION STATEMENT (of the obstroct eteed In lloi EL.C Itdtee otRpr Distribution of this document is unlimited. SEP 3 1980M IS. SUPPLEMENTARY NOTES Prepared and accepted for publication in Inorganic Chemistry. 19. KEY WORDS (Continue an toeter side it necesay and idarntifF by Weekh aimb..) Photochemistry, catalysis, metal carbonyls, photocatalytic activity, hydrosilation. 24ABSTRACT (Cetlmae on revre side It necessary and identify by block ONMAb.) Photochemistry of R'3SiCo(CO), ' (R = Et, Ph) in hydrocarbon solvents shows that the dominant primarf excited state process is loss of CO, not cleavage of the SSi-Co bond. The 366 nm quantum yield for CO substitution by P(OPh)7 is ~30.284 0.05 to give R'ISiCo(CO)'3P(OPh)3i. Irradiation of R3SiCO(CO), in the L ~ presence of 0.1 M HSiR 3 gives R'3S1Co ( CO0) with a quantum yield nearly th