Clément Sébastien, Aly Shawkat M, Bellows Diana, Fortin Daniel, Strohmann Carsten, Guyard Laurent, Abd-El-Aziz Alaa S, Knorr Michael, Harvey Pierre D
Institut UTINAM UMR CNRS 6213, Université de Franche-Comté, 16 route de Gray, 25030 Besançon, France.
Inorg Chem. 2009 May 4;48(9):4118-33. doi: 10.1021/ic8023315.
The homodinuclear [ClM(mu-dppm)(2)MCl] complexes 1 (M = Pd) and 2 (M = Pt) react with RNC ligands (R = Ph, xylyl, p-tolyl, p-C(6)H(4)iPr) to provide the A-frame [ClPd(mu-dppm)(2)(mu-C=N-R)PdCl] (R = Ph (5a), xylyl (5b)), [ClPt(mu-dppm)(2)(mu-C=N-R)PtCl] (R = p-tolyl (4a); p-C(6)H(4)iPr (4b)), and the d(9)-d(9) M(2)-bonded [ClPt(mu-dppm)(2)Pt(CN-R)]Cl (R = xylyl (3a); p-C(6)H(4)iPr (3b)) complexes. The heterodinuclear [XPd(mu-dppm)(2)PtX] complexes 6a (X = Cl) and 6b (X = I) react with RNC (R = o-anisyl) to form the A-frame [XPd(mu-dppm)(2)(mu-C=N-R)PtX] (X = Cl (9); I (10a)) and M(2)-bonded [ClPt(mu-dppm)(2)Pt(CN-R)]Cl (10b) complexes. The dangling ligand-containing complex ClPd(mu-dppm)(2)Pt(eta(1)-dppm=O) (7) reacts with xylyl-NC stoichiometrically to produce the dicationic salt (xylyl-NC)Pd(mu-dppm)(2)Pt(eta(1)-dppm=O)(2) (8). Parameters ruling the coordination site terminal versus bridging are discussed. The precursor 10a reacts with RNC (R = o-anisyl, tBu) to form the heterobimetallic bis(isonitrile) [IPd(mu-dppm)(2)(mu-C=N-o-anisyl)Pt(CN-R)]I complexes 11b and 12, respectively, demonstrating the site selectivity of the second CNR ligand coordination, Pd versus Pt. The X-ray structures of 11b and 12 were obtained. Complex 12 is the first example of an A-frame system of the Ni-triad bearing two different isocyanide ligands. Several d(9)-d(9) terminal and d(8)-d(8) A-frame homo- and heterodinuclear complexes in 2-MeTHF at 77 K were studied by UV-vis and luminescence spectroscopy. Assignments for the lowest energy absorption and emission bands are made on the basis of density functional theory and time-dependent density functional theory computations.
同双核[ClM(μ-dppm)₂MCl]配合物1（M = Pd）和2（M = Pt）与RNC配体（R = Ph、二甲苯基、对甲苯基、对-C₆H₄iPr）反应，生成A框架[ClPd(μ-dppm)₂(μ-C=N-R)PdCl]（R = Ph (5a)、二甲苯基 (5b)）、[ClPt(μ-dppm)₂(μ-C=N-R)PtCl]（R = 对甲苯基 (4a)；对-C₆H₄iPr (4b)）以及d⁹-d⁹ M₂键合的[ClPt(μ-dppm)₂Pt(CN-R)]Cl（R = 二甲苯基 (3a)；对-C₆H₄iPr (3b)）配合物。异双核[XPd(μ-dppm)₂PtX]配合物6a（X = Cl）和6b（X = I）与RNC（R = 邻茴香基）反应，形成A框架[XPd(μ-dppm)₂(μ-C=N-R)PtX]（X = Cl (9)；I (10a)）以及M₂键合的[ClPt(μ-dppm)₂Pt(CN-R)]Cl（10b）配合物。含悬挂配体的配合物ClPd(μ-dppm)₂Pt(η¹-dppm=O)（7）与二甲苯基-NC按化学计量比反应，生成二价阳离子盐(二甲苯基-NC)Pd(μ-dppm)₂Pt(η¹-dppm=O)₂（8）。讨论了决定配位位点是末端还是桥连的参数。前体10a与RNC（R = 邻茴香基、tBu）反应，分别形成异双金属双（异腈）[IPd(μ-dppm)₂(μ-C=N-邻茴香基)Pt(CN-R)]I配合物11b和12，证明了第二个CNR配体配位的位点选择性，即Pd对Pt。获得了11b和12的X射线结构。配合物12是含两种不同异氰化物配体的镍三元组A框架体系的首个实例。在77 K下，通过紫外可见光谱和发光光谱研究了2-MeTHF中的几种d⁹-d⁹末端和d⁸-d⁸ A框架同双核和异双核配合物。基于密度泛函理论和含时密度泛函理论计算，对最低能量吸收和发射带进行了归属。
