Synthesis, structures and derivative chemistry of group 11 and 15 metallacarboranes

Abstract

A set of reaction systems of MX/$Tl_2CB_9H_11$/$EPh_3$/QCl (M = Group 11 metal, X = halide, E = Group 15 atoms, and Q =organic cation) has been investigated. The foregoing research work led to the discovery of new classes of Group 11 metallacarboranes and Group 15 metallacarboranes. From the reaction of Cu$(PPh_3)_3$ Cl and $Tl_2C_2H_9H_11$, a novel thallium salt of cupracarborane [closo-3-($PPh_3$)-3,1,2-$CuC_2B_9H_11$] Tl (2.Tl) was prepared and found to be a useful synthon to heterodinuclear cupracarboranes. Various reaction features were developed in the reaction system of 2 . Tl and transition metal halides. Direct complexation of $[Ag(PPh_3)]^+$ with $[(PPh_3) CuC_2B_9H_11]^-$ was observed in case of 2.Tl/AgBr/$PPh_3$, affording a novel bimetallic complex [closo-exo-4,8-{$(μ-H)_2Ag(PPh_3)$-3,1,2-$CuC_2B_9H_9$] (5). A set of reactions of 2.Tl with Vaska``s complex and its congener analogues afforded cage-transferred dinuclear complexes [exo-4-{(μ-H)Cu($PPh_3$)}-3-(CO)-3-($PPh_3$)-closo-3,1,2-$MC_2B_2H_10$] (M: Co, 14; Rh, 15;Ir, 16) having bonding interaction between Group 9 metals and copper. Another reaction of 2.Tl and $Mn(CO)_5Br$ also resulted in cage transfer, yielding [exo-8-{μ-H)Cu($PPh_3$)}-3-(μ-CO)-3,3-$(CO)_2$-clso-3,1,2-$MnC_2B_9H_10$]. With Group 9 metal halides of higher oxidation state such as $[Rh(η^5-C_5Me_5)Cl_2]_2$ and $Co(PPh_3)_2Cl_2$, 2.Tl reacts to give transmetallated dicarbollyl complexes of Rh(III) and Co(III). The reaction of 2.Tl and $FeCl_2$ in the presence of $PPh_3$ revealed that some of the carborane in 2 was partially partilly protonated possibly due possibly to the residual water molecule in the reaction solvent and some was transmetallated to Fe with concomittant oxidation of Fe(II) to Fe(III), providing exo-nido cupracarborane [9,10exo-{$(μ-H)_2Cu(PPh_3)_2$}-nido-7,8-$C_2B_9H_10$] (4) and a sandwich ferracarborane [commo-3,3``-Fe{3,1,2-Fe$(C_2B_9H_11)_2$}]-, respectively. Another reaction of 2.Tl and [$Mo(CO)_5Cl$](PPN)...