(β-Diketiminato)cadmium Bis(trimethylsilyl)amide: Facile Access to Low-Coordinate Cadmium Complexes

Utilising an anilido-imino ligand to stabilise zinc-phosphanide complexes: reactivity and fluorescent properties

A series of zinc complexes bearing the anilido-imino ligand [(o-C6H4{N(C6H3iPr2)}{C(CH3) = NC6H3iPr2})] [(LDipp)ZnX] has been generated. This includes two amide derivatives, [(LDipp)Zn(N{SiMe3}2)] and [(LDipp)Zn(NH{Dipp})] and two phosphanide derivatives, [(LDipp)ZnPCy2] and [(LDipp)ZnPPh2]. The chemistry of the phosphanide complexes towards chalcogens was examined, with sulfur, selenium and tellurium oxidising the phosphorus centre of the dicylohexylphosphanide complex [(LDipp)ZnPCy2] to form [(LDipp)Zn(E)2PCy2] (E = S, Se, Te). Addition of tellurium to the diphenylphosphanide complex [(LDipp)ZnPPh2] results in formation of Ph2PPPh2 and [(LDipp)ZnTeZn(LDipp)]. The absorption and emission properties of these complexes was examined and the quantum yields are highly dependent upon the non-ancillary ligand X.

Carbodiimides as catalysts for the reduction of a cadmium hydride complex

A rare terminal cadmium hydride complex has been synthesised. Reduction to the cadmium(i) dimer complex was achieved upon treatment with carbodiimides.

Tin and Lead Phosphanido Complexes: Reactivity with Chalcogens

The reactivity of tin and lead phosphanido complexes with chalogens is reported. The addition of sulfur to [(BDI)MPCy₂] (M = Sn, Pb; BDI = CH{(CH₃)CN-2,6-iPr₂C₆H₃}₂) results in the formation of phosphinodithioates [(BDI)MSP(S)Cy₂] regardless of the conditions; however, when selenium is added to [(BDI)MPCy₂], a selenium insertion product, phosphinoselenoite [(BDI)MSePCy₂], can be isolated. This compound readily reacts with additional selenium to form the phosphinodiselenoate complex [(BDI)MSeP(Se)Cy₂]. In contrast, the addition of selenium to [(BDI)SnP(SiMe₃)₂] results in the formation of the heavy ether [(BDI)SnSeSiMe₃]. Differences in the solution and solid-state molecular species of tin phosphinoselenoite and phosphinodiselenoate complexes were probed using multinuclear solution and solid-state NMR spectroscopy.

Cadmium complexes bearing Me2N^E^O- (E = S, Se) organochalcogenoalkoxides and their zinc and mercury analogues

Heteroleptic zinc and cadmium complexes of the type [{^Me₂N^E^O^R₂}M-Nu]_n (M = Zn, Cd; E = S, Se; R = CH₃, CF₃; Nu = N(SiMe₃)₂, I, Cl; n = 1-2) were prepared by reacting the alcohol proteo-ligands {^Me₂N^E^O^R₂}H with [M(N(SiMe₃)₂)₂] (M = Zn, Cd) or [XMN(SiMe₃)₂] (M = Zn, X = Cl; M = Cd, X = I) in an equimolar ratio. These group 12 metal complexes were characterised in solution by multinuclear NMR spectroscopy and their solid-state structures were determined by X-ray diffractometry. The ligands {^Me₂N^E^O^(CH₃)₂}^- bearing CH₃ groups in α position to the alkoxide behave as κ²-O,E-bidentate moieties (E = S, Se) and form centro-symmetric dinuclear O-bridged heteroleptic alkoxo-amido complexes both with zinc and cadmium, with four-coordinate metal centres resting in tetrahedral environments. By contrast, complexes supported by the CF₃-substituted {^Me₂N^E^O^(CF₃)₂}^- crystallise as tetrahedral mononuclear species, with tridentate κ³-N,O,E-coordinated ligands. These structural differences resulting from changes in the ligand skeleton and in the electron-donating properties of the alkoxide were also observed in solution. Attempts to prepare congeneric heteroleptic mercury complexes from [Hg(N(SiMe₃)₂)₂] unexpectedly only afforded homoleptic bis(alkoxide)s such as [{^Me₂N^S^O^(CF₃)₂}₂Hg]. Owing to the strong Hg-C bond, treatment of [PhHgN(SiMe₃)₂] with {^Me₂N^S^O^(CF₃)₂}H afforded the heteroleptic, T-shaped [{^Me₂N^S^O^(CF₃)₂}HgPh] mercuric alkoxide upon elimination of hexamethyldisilazane. [{^Me₂N^S^O^(CF₃)₂}₂Hg] and [{^Me₂N^S^O^(CF₃)₂}HgPh] constitute very rare examples of structurally characterised mercuric alkoxides.