Amidinatotetrylenes Donor Functionalized on Both N Atoms: Structures and Coordination Chemistry.

E(hmds)(bqfam) (E = Ge (), Sn (); hmds = N(SiMe), bqfam = (quinol-8-yl)formamidinate), which are amidinatotetrylenes equipped with quinol-8-yl fragments on the amidinate N atoms, have been synthesized from the formamidine Hbqfam and Ge(hmds) or SnCl(hmds). Both and are fluxional in solution at room temperature, as the E atom oscillates from being attached to the two amidinate N atoms to being chelated by an amidinate N atom and its closest quinolyl N atom (both situations are similarly stable according to density functional theory calculations). The hmds group of and is still reactive and the deprotonation of another equivalent of Hbqfam can be achieved, allowing the formation of the homoleptic derivatives E(bqfam) (E = Ge, Sn). The reactions of and with [AuCl(tht)] (tht = tetrahydrothiophene), [PdCl(MeCN)], [PtCl(cod)] (cod = cycloocta-1,5-diene), [Ru(CO)] and [Co(CO)] have been investigated. The gold(I) complexes [AuCl{κ-E(hmds)(bqfam)}] (E = Ge, Sn) have a monodentate κ-tetrylene ligand and display fluxional behavior in solution the same as that of and . However, the palladium(II) and platinum(II) complexes [MCl{κ-ECl(hmds)(bqfam)}] (M = Pd, Pt; E = Ge, Sn) contain a κ-chloridotetryl ligand that arises from the insertion of the tetrylene E atom into an M-Cl bond and the coordination of an amidinate N atom and its closest quinolyl N atom to the metal center. Finally, the binuclear ruthenium(0) and cobalt(0) complexes [Ru{μ-κ-E(hmds)(bqfam)}(CO)] and [Co{μ-κ-E(hmds)(bqfam)}(μ-CO)(CO)] (E = Ge, Sn) have a related κ-tetrylene ligand that bridges two metal atoms through the E atom. For the κmetal complexes, the quinolyl fragment not attached to the metal is pendant in all the germanium compounds but, for the tin derivatives, is attached to (in the Pd and Pt complexes) or may interact with (in the Ru and Co complexes) the tin atom.