Cleavage of formamidinate ligands on a Ta=Ta double bond: formation of HxCNAryl (x = 0 and 1) and arylimido-bridged complexes

The formamidinate anion (eta2-DPhF)2Ta(mu-MPh)(mu-eta2-CN-Ph)Ta(eta2-DPhF)2 was synthesized by the reaction of LiDPhF with Ta2Cl6(SMe2)3 and zinc. The reaction of LiDPhF and Ta2Cl6(Sme2)3 with LidTolF and Na/Hg generated (eta2-DTolF)Ta(mu-NToL)(mu-eta2-CNTol)(mu-DTolF)2Ta(eta-DTolF). The formamidinate anions are composed of C-N units that exhibit edge-on mode in the CNPh group bonds to the tantalum atoms. Furthermore, the formation of the compounds was characterized by the cleavage of the C-N bonds.