Alkyl-metal and aryl-metal bond chemistry in coordinately unsaturated polynuclear metal complexes.
A new class of coordinately unsaturated polynuclear rhodium and iridium alkyl, benzyl, and aryl derivatives of the form [RM(1,5-cyclooctadiene)](x) have been prepared by the reaction of the organolithium reagent with the cyclooctadienemetal chlorides at -78 degrees C. The x-ray crystal structure of [mu-CH(3)Rh (1,5-cyclooctadiene)](2) is reported. The analogous iridium dimer decomposes by an initial sequence of alpha-hydrogen abstraction and then reductive elimination of hydrogen to give [mu-CH(2)Ir(1,5-cyclooctadiene)](2). Formed in high yield by the decomposition of the ethylrhodium complex was [HRh(C(8)H(11))](4), a tetrahedral cluster with face-bridging hydride ligands. Also discussed are the reactivities of the benzyl and phenyl derivatives. Unique reaction pathways for C-H bond activation and scission in this chemistry are delineated.
Schmidt
G F
GF
Department of Chemistry, University of California, Berkeley, California 94720.
Muetterties
E L
EL
Beno
M A
MA
Williams
J M
JM