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A new type of trans‐dichloro‐Ir(III) complexes derived from non‐symmetrical NacNac‐type ligands was unexpectedly obtained as the main reaction product from the former ligands and the dimeric species [Ir(COD)Cl2]. One equivalent of LH was reacted with an excess of [Ir(COD)Cl]2 in dichloromethane or toluene as solvent and at room temperature. The general formula of the product is [IrCl2(COD)L] and was isolated as a sole product instead of the expected Ir(I) compound [Ir(COD)L]; all the new Ir(III) were prepared in high yields as microcrystalline solids. They were all stable under laboratory atmosphere, lasting for weeks in solution and for months in solid state. The structure of each compound was examined by 1D and 2D nuclear magnetic resonance (NMR) and high‐resolution mass spectrometry (HRMS). Complex 1k was selected for an X‐ray diffraction study. Finally, an evaluation was made of the catalytic activity of all complexes in the transfer hydrogenation reaction of ketones and imines. [ABSTRACT FROM AUTHOR]

The bis(silyl)triazene compound 2,6-(Me3Si)2-4-Me-1-(NNNC4H8)C6H2 ( 4) was synthesized by double lithiation/silylation of 2,6-Br2-4-Me-1-(NNNC4H8)C6H2 ( 1). Furthermore, 2,6-bis[3,5-(CF3)2-C6H3]-4-Me-C6H2-1-(NNNC4H8)C6H2 derivative 6 can be easily synthesized by a C,C-bond formation reaction of 1 with the corresponding aryl- Grignard reagent, i.e., 3,5-bis[(trifluoromethyl)phenyl]magnesium bromide. Reactions of compound 4 with KI and 6 with I2 afforded in good yields novel phenyl derivatives, 2,6-(Me3Si)2-4-MeC6H2I and 2,6-bis[3,5-(CF3)2C6H3]-4-MeC6H2I ( 5 and 7, resp.). On the other hand, the analogous m-terphenyl 1,3-diphenylbenzene compound 2,6-bis[3,5-(CF3)2C6H3]C6H3I ( 8) could be obtained in moderate yield from the reaction of (2,6-dichlorophenyl)lithium and 2 equiv. of aryl- Grignard reagent, followed by the reaction with I2. Different attempts to introduce the tBu (Me3C) or neophyl (PhC(Me)2CH2) substituents in the central ring were unsuccessful. All the compounds were fully characterized by elemental analysis, melting point, IR and NMR spectroscopy. The structure of compound 6 was corroborated by single-crystal X-ray diffraction measurements. [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]