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Abstract: The reaction of LiArMe6 [ArMe6 C6H3-2,6(C6H2-2,4,6-Me3)2] with InCl, [In(InI4)], InCl in the presence of LiI, or ‘GaI’ in toluene solution resulted in the isolation of the 1,2-diaryl-1,2-dihalogen derivatives [{InCl(ArMe6)}2]2 (1), [{InI(ArMe6)}2]2 (2), [{In4Cl2I2(ArMe6)4}] (3), and [{GaI(ArMe6)}2] (4). The indium derivatives 1–3 were isolated as tetrametallic complexes formed via the almost symmetric bridging by four halides of two In–In bonded, ArMe6In–InArMe6 moieties. In 1, the In4Cl4 core features almost parallel In–In units, linked by four almost symmetrically bridging chlorides. This yields a structure formed from two folded In2Cl2 rings, and two six-membered In4Cl2 boat-shaped rings that have common In–Cl edges. The structures of 2 and 3 also feature two ArMe6InInArMe6 units bridged by four halides. However, there is a large torsion angle between the two In–In vectors, so that the In4I4 (2) and In4Cl2I2 (3) cores are formed from four five-membered In3I2 (2) or In3ClI (3) rings. Compound 4 has a simple Ga–Ga bonded dimeric structure, in which the gallium atoms are three coordinated, being bonded to each other as well as to an iodine and an ArMe6 ligand. All the compounds were characterized by 1H and 13C {1H} NMR spectroscopy, and by X-ray crystallography. The structural differences between the gallium and indium derivatives is probably a result of the larger size and greater Lewis acidity of the indium centers. [Copyright &y& Elsevier]

Abstract: The nickel (0) compound Ni(COD)(GaAr′)2 (Ar′ = C6H3–2,6-(C6H3-2,6-i-Pr2)2), 1, was synthesized by the reaction of Ni(COD)2 (COD = 1,5-cyclooctadiene) with (GaAr′)2. Compound 1 reacted with ethylene at 25 °C and at 1 atm pressure to give the bimetallic cluster [Ni2(GaAr′)2(η1:η1-μ2-C2H4)], 2, through the incorporation of one molecule of ethylene and displacement of COD. The structure of 2 featured an unusual Ni2Ga2C2 core bicyclic structure in which the C2H4 moiety bridges the Ga···Ga edge of a Ga2Ni2 tetrahedron. The galliums each carry an η1-bonded Ar′ substituent which complexes the nickel atom by an η6–π interaction with one of its flanking Ar’ rings. [Copyright &y& Elsevier]

Graphical abstract Neutral and cationic nickel, palladium and platinum complexes containing a new N,N,S-tridentate ligand have been prepared and characterized. The structure of the ligand and eight complexes was determinate by X-ray crystallographic analysis. Ligand can be both mono- or di-deprotonated under mild reaction conditions. Studies in Heck reaction and antiproliferative activities are reported. Abstract Organometallic and coordination nickel, palladium and platinum complexes, neutral and cationic, with general formula [M(κ3-SacNac)X] and [M(κ3-SacNac)L′][BPh 4 ] (where M = Ni, Pd and Pt, X = Me, Cl, 1 – 6 ; M = Ni, X = N 3 , SMe, 7 – 8 ; M = Pd, X = I, 13 ; M = Ni and Pd, L′ = PPh 3 , 9 – 10 ; M = Ni and Pt, X = PMe 3 , dmso, 11 – 12) containing a new SacNac N,N,S-tridentate ligand [C 6 H 5 (S)CCH 2 C(N-CH 2 CH 2 NHC 6 H 5)CH 3 ] were synthetized and obtained as microcrystalline solids. Compounds 2 – 13 were fully characterized by elemental analysis, IR, 1D and 2D NMR spectroscopy. The structure of the ligand and eight complexes was determined by X-ray crystallographic analysis. The ligand can be both mono- or bi-deprotonated under mild reaction conditions. Results in Heck reaction and antiproliferative activities are reported. [ABSTRACT FROM AUTHOR]

Abstract: Nickel and palladium organometallic [M(R)(NNO)] (R=CH2CMe2C6H5; M=Pd, 1 , Ni, 2 ; R=Me, M=Pd, 3 , Ni, 4 ; R=CH2SiMe3, M=Ni, 5 ) and coordination [MCl(NNO)] (M=Pd(II), 6, Ni(II), 7), [Ni(NNO)2], 8, complexes containing the potentially tridentate Schiff base NNO-donor ligand which is the condensation product of 2-hidroxynaphtaldehyde and N-benzylethylenediamine, were prepared and characterized by elemental analysis, IR and NMR spectroscopy. The crystal structure of 8 was determined by single X-ray diffraction measurements. Complexes 1–6 had a square planar structure with the ligand being tridentate through the NNO atoms. On the other hand compound 7 presented a conformational equilibrium in dissolution at room temperature and a rigid square-planar structure at 220K. The crystal structure of 8 indicated a monoclinic lattice, with a P2(1)/c space group, a =13.1799(8), b =14.5556(9), c =17.5018(11)Å, b =98.0420 (10)°, Z =4. The central Ni atom in 8 was in a N4O2 coordination sphere formed by two NNO Schiff base ligands. In this structure two of the Ni–N bonds trans to the oxygen atoms were significantly longer than the other two Ni–N bonds, 2.0175(17), 2.2761(17) versus 2.0070(17), 2.1794(14)Å. The two oxygen phenol atoms of the chelating ligands were cis and the distances of the Ni(II)–O(phenol) bond were 2.0410(14) and 2.0415(14)Å, respectively. [Copyright &y& Elsevier]