Substitution and reaction chemistry of cobalt complexes supported by [N2P2] ligands.
The coordination chemistry of mono- and divalent cobalt complexes supported by the monoanionic multidentate ligands, [N(2)P(2)] (where [N(2)P(2)] = (t)BuN((-))SiMe(2)N(CH(2)CH(2)P(i)Pr(2))(2)) and [N(2)P(2)(tolyl)] (where [N(2)P(2)(tolyl)] = MeC(6)H(4)N((-))SiMe(2)(CH(2)CH(2)P(i)Pr(2))(2)), is presented. The Co(II) halide complex [N(2)P(2)]CoI (2) serves as a precursor to the alkyl, hydride, and amide species [N(2)P(2)]CoMe (3), [N(2)P(2)]CoCH(2)SiMe(3) (4), [N(2)P(2)]CoH (5), [N(2)P(2)]CoNHPh (10), and [N(2)P(2)]CoNHC(6)H(4)Me (11). Reduction of 2 results in the formation of a stable, monomeric Co(I) species, [N(2)P(2)]Co (6). Compound 6 can be trapped with CO to form either [N(2)P(2)]Co(CO) (7) or [(t)BuN(C=O)SiMe(2)N(CH(2)CH(2)P(i)Pr(2))(2)]Co(CO)(2) (8) depending on the number of equivalents of CO introduced. Compound 6 also serves as a precursor to transient Co(III) imido species. The Co(II) halide complex [N(2)P(2)(tolyl)]CoI (16) is synthesized through an analogues reaction to that of 2. Reduction of 16 results in the formation of [N(2)P(2)(tolyl)]Co (17), and differences in the coordination and reaction chemistry of 6 and 17 are described.
Chomitz
Wayne A
WA
Department of Chemistry, University of California, Berkeley, California 94720-1460, USA.
Arnold
John
J