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Synthesis and structural characterization of two heterodinuclear ZnII-LnIII complexes with the formula [ZnLn(HL)(µ-OAc)(NO3)2(H2O)x(MeOH)1-x]NO3 · n H2O · n MeOH [Ln = Pr (1), Nd (2)] and the crystal and molecular structure of [ZnNd(HL)(µ-OAc)(NO3)2(H2O)] [ZnNd(HL)(OAc)(NO3)2(H2O)](NO3)2 · n H2O · n MeOH (3) are reported. The asymmetrical compartmental ligand (E)-2-(1-(2-((2-hydroxy-3-methoxybenzylidene)amino)-ethyl)imidazolidin-2-yl)-6-methoxyphenol (H2L) is formed from N1,N3-bis(3-methoxysalicylidene)diethylenetriamine (H2valdien) through intramolecular aminal formation, resulting in a peripheral imidazoline ring. The structures of 1–3 were revealed by X-ray crystallography. The smaller ZnII ion occupies the inner N2O2 compartment of the ligand, whereas the larger and more oxophilic LnIII ions are found in the outer O2O2' site. Synthesis and structural characterization of two heterodinuclear ZnII-LnIII complexes (Ln = Pr, Nd) bearing an asymmetrical compartmental ligand formed in situ from N1,N3-bis(3-methoxysalicylidene)diethylenetriamine (H2valdien) through intramolecular aminal formation are reported. [ABSTRACT FROM AUTHOR]

The bottom-up synthesis of organometallic zinc clusters is described. The cation {[Zn10](Cp*)6Me}+ ( 1) is obtained by reacting [Zn2Cp*2] with [FeCp2][BAr4F] in the presence of ZnMe2. In the presence of suitable ligands, the high reactivity of 1 enables the controlled abstraction of single Zn units, providing access to the lower-nuclearity clusters {[Zn9](Cp*)6} ( 2) and {[Zn8](Cp*)5(tBuNC)3}+ ( 3). According to DFT calculations, 1 and 2 can be described as closed-shell species that are electron-deficient in terms of the Wade-Mingos rules because the apical ZnCp* units that constitute the cluster cage do not have three, but only one, frontier orbitals available for cluster bonding. Zinc behaves flexibly in building the skeletal metal-metal bonds, sometimes providing one major frontier orbital (like Group 11 metals) and sometimes providing three frontier orbitals (like Group 13 elements). [ABSTRACT FROM AUTHOR]

The triangular clusters [Zn3Cp*3]+ and [Zn2CuCp*3] were obtained by addition of the in situ generated, electrophilic, and isolobal species [ZnCp*]+ and [CuCp*] to Carmona's compound, [Cp*ZnZnCp*], without splitting the ZnZn bond. The choice of non-coordinating fluoroaromatic solvents was crucial. The bonding situations of the all-hydrocarbon-ligand-protected clusters were investigated by quantum chemical calculations revealing a high degree of σ-aromaticity similar to the triatomic hydrogen ion [H3]+. The new species serve as molecular building units of Cu nZn m nanobrass clusters as indicated by LIFDI mass spectrometry. [ABSTRACT FROM AUTHOR]

The synthesis and characterisation of the solvent-stabilized salt [Zn2(THF)6]2+[BAr4F]2− (1) is presented, which features the dizinc dication [Zn2]2+ as an analogue of the calomel dication [Hg2]2+. The labile tetrahydrofuran (THF) solvate molecules of 1 can be readily substituted by other ligands. Reaction with the strong donor ligand PMe3 (Me = CH3) leads to the Zn(ii) complex [Zn(PMe3)4]2+[BAr4F]2− by disproportionation, while the π-acceptor-ligand phenylisocyanide (PhNC) gives the substitution product [Zn2(PhNC)6]2+[BAr4F]2− (2) with an intact Zn–Zn bond. [ABSTRACT FROM AUTHOR]

Abstract: Reactions of the sterically encumbered N-heterocyclic carbene IPr (IPr=1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene, [:C{[N(2,6-iPr2C6H3)]CH}2]) (1) with TiX4 (X=Cl, F) in diethyl ether or THF afford the metal halide mono- and bis-carbene complexes, [Cl4Ti-C{N(2,6- i Pr2C6H3)CH}2] (2), [Cl4Ti{C{N(2,6- i Pr2C6H3)CH}2}2] (3) and [F4Ti{C{N(2,6- i Pr2C6H3)CH}2}2] (4). Compounds 2–4 have been completely characterized by elemental analysis, NMR spectroscopic methods (1H, 13C and 19F NMR) and single crystal X-ray structure determination. Furthermore, the reaction of [Cl4Ti-C{N(2,6- i Pr2C6H3)CH}2] (2) with ZnMe2 yields monomeric [ZnCl2·IPr] (5), involving the transfer of carbene and chlorido ligands from Ti (IV) to Zn(II). [Copyright &y& Elsevier]

Reactions of homoleptic isonitrile ligated complexes or clusters of d10-metals with the potent carbenoid donor ligand GaCp* are presented (Cp* = pentamethylcyclopentadienyl). Treatment of [Ni4(CNt-Bu)7], [{M(CNR)2}3] (M = Pd, Pt) and [Pd(CNR)2Me2] (R = t-Bu, Ph) with suitable amounts of GaCp* lead to the formation of the heteroleptic, tri- and tetranuclear clusters [Ni4(CNt-Bu)7(GaCp*)3] (1), [{M(CNt-Bu)}3(GaCp*)4] (M = Pd: 2a, Pt: 2b), and [{Pd(CNR)}4(GaCp*)4] (R = t-Bu: 3a, Ph: 3b). The reactions involve isonitrile substitution reactions, GaCp* addition reactions, and cluster formation reactions. The new compounds were investigated for their ability to undergo Ga/Zn exchange reactions when treated with ZnMe2. The novel tetranuclear Zn-rich clusters [Ni4GaZn7(Cp*)2Me7(CNt-Bu)6] (4) and [{Pd(CNR)}4(ZnCp*)4(ZnMe)4] (R = t-Bu: 5a, Ph: 5b) were obtained and isolated. The electronic situation and geometrical arrangement of atoms of all compounds will be presented and discussed. All new compounds are characterized by solution 1H, 13C NMR and IR spectroscopy, elemental analysis (EA), liquid injection field desorption ionization mass spectrometry (LIFDI-MS) as well as single crystal X-ray crystallography. [ABSTRACT FROM AUTHOR]