DECOMPOSITION REACTIONS OF SQUARE-PLANAR BIS-ARYL-COBALT(II) COMPLEXES

Article abstract of DOI:10.1016/S0022-328X(00)95262-8

The organocobalt complexes , with (a) L=PEtPh2 and R=2,3,5,6-C6HCl4, 2,4,6-C6H2Cl3 and 2,6-C6H3Cl2; and (b) R=2,4,6-C6H2Cl3 and L=PEt3, PEt2Ph, 1/2dpe, 3,5-lut and 1/2bipy, have been obtained by reaction of RMgX with or by ligand exchange from .The decompositions in benzene and carbon tetrachloride, and under oxidative conditions have been studied.In benzene solutions, the stability decreases with decrease in the number of chlorine atoms in R.A mixture of R-H and R-R is obtained in a ratio which depends on the nature of L, the configuration of the complex, and the presence of oxidants.The thermal decomposition takes place through a tricoordinate intermediate "CoR2L", when L=phosphine, or directly from when L=amine.The oxidatively induced decomposition takes place through a cobalt(III) intermediate, which gives R-R when L=phosphine or R-X (X=H, Br) when L=amine.The process is intramolecular in all cases.