Acceptor Pincer Chemistry of Osmium: Catalytic Alkane Dehydrogenation by (<sup>CF<sub>3</sub></sup>PCP)Os(cod)(H)
作者:Brian C. Gruver、Jeramie J. Adams、Navamoney Arulsamy、Dean M. Roddick
DOI:10.1021/om400823s
日期:2013.11.11
The alkane dehydrogenation activity of (CF3PCP)Os(cod)H was examined: under identical conditions to previously studied (CF3PCP)Ru(cod)H (1:1 cyclooctane/tert-butylethylene, 200 °C), the initial turnover rate for cyclooctene production was 1520 h–1, 75% the rate observed for the ruthenium analogue, but with significantly enhanced catalyst lifetime. Acceptorless cyclodecane dehydrogenation under reflux
作者:Jeramie J. Adams、Ade Lau、Navamoney Arulsamy、Dean M. Roddick
DOI:10.1021/om1008633
日期:2011.2.28
syntheses of Ir(I) and Ir(III) complexes incorporating the electron-poor pincerligand (1,3-C6H3(CH2P(CF3)2)2) (CF3PCP) are reported. Under mild conditions, the reaction of CF3PCPH with [(cod)Ir(μ-Cl)]2 in benzene gave polymeric [(cod)IrCl(μ-CF3PCPH)]n, which was structurally characterized. Thermolysis of [(coe)2Ir(μ-Cl)]2 or [(cod)Ir(μ-Cl)]2 with CF3PCPH in toluene at 120 °C resulted in metalation to give
An investigation of ethylene rotational barriers for 5-coordinate d 8 metal bis-ethylene complexes
作者:Jeramie J. Adams、Navamoney Arulsamy、Dean M. Roddick
DOI:10.1016/j.poly.2014.08.058
日期:2014.12
which confirms a rare example of axial and equatorial ethylene coordination in a TBP coordination environment. DFT studies indicate a moderate barrier to ethylenerotation for the equatorial C2H4 group (ΔG‡ = 19.0 kcal mol−1), and a negligible rotationalbarrier for the axial C2H4 (ΔG‡ = 1.2 kcal mol−1). DFT analyses of ethylenerotationalbarriers for a series of known symmetrical (equatorial/equatorial)
据报道(CF 3 PCP)Ir(C 2 H 4)2的成功分离和结构表征,这证实了在TBP配位环境中稀少的轴向和赤道乙烯配位的例子。DFT研究表明中度障碍乙烯旋转为赤道C ^ 2 ^ h 4组(Δ ģ ‡ = 19.0千卡摩尔-1),和用于轴向℃的可忽略的旋转屏障2 ħ 4(Δ ģ ‡ = 1.2千卡摩尔- 1个)。一系列已知的对称(赤道/赤道)和非对称(赤道/轴向)双亚乙基Ir(I)配合物的乙烯旋转势垒的DFT分析与先前报道的实验旋转势垒一致。在非对称系统([9] aneS 3)Ir(C 2 H 4)2 +和(Tp)Ir(C 2 H 4)2的情况下,未观察到单独的赤道C 2 H 4旋转势垒,原因是轴向和赤道乙烯配位位置的构象交换方便。未观察到(CF 3 PCP)Ir(C 2 H4)2。
Acceptor CF3PCPH pincer reactivity with (PPh3)3Ir(CO)H
作者:Jeramie J. Adams、Navamoney Arulsamy、Dean M. Roddick
DOI:10.1039/c1dt10952a
日期:——
The syntheses of Ir(I) and Ir(III) complexes incorporating the electron-withdrawing pincer ligand (1,3-C6H4(CH2P(CF3)2)2) (CF3PCPH) with (PPh3)3Ir(CO)H and subsequent chemistry are reported. Under ambient conditions, reaction of 1 equiv. CF3PCPH with (PPh3)3Ir(CO)H gave the mono-bridged complex [Ir(CO)(PPh3)2(H)]2(μ-CF3PCPH) (1). Reaction of (PPh3)3Ir(CO)H with excess CF3PCPH and MeI gave the doubly-bridged complex [Ir(CO)(PPh3)(H)]2(μ-CF3PCPH)2 (2), whereas the tetrameric oligomer [Ir(CO)(PPh3)(H)]4(μ-CF3PCPH)4 (2-sq) was obtained from a 1 : 1 ligand : metal mixture in benzene in the presence of excess MeI. At higher temperatures (165 °C) the reaction of CF3PCPH with (PPh3)3Ir(CO)H afforded the 5-coordinate Ir(I) complex (CF3PCP)Ir(CO)(PPh3) (3). Complex 3 shows mild catalytic activity for the decarbonylation of 2-naphthaldehyde in refluxing diglyme (162 °C).
作者:Jeramie J. Adams、Brian C. Gruver、Rose Donohoue、Navamoney Arulsamy、Dean M. Roddick
DOI:10.1039/c2dt31234d
日期:——
A series of new acceptor pincer Ru(II) complexes are reported. The carbonyl complex (CF3PCP)Ru(CO)Cl2−Et3NH+ is obtained from the reaction of CF3PCPH with [(cod)Ru(μ-Cl)2]n. Chloride displacement with CF3PCPH, CO, PPh3, or C2H4 gave complexes of the type (CF3PCP)Ru(CO)(L)Cl, or in the case of CF3PCPH, the bridged dimeric complex [(CF3PCP)Ru(CO)Cl]2(μ-CF3PCPH). Chloride abstraction from (CF3PCP)Ru(CO)(L)Cl, L = CO or PPh3 by (Et3Si)2(μ-H)+B(C6F5)4− followed by Et3N addition produced (CF3PCP)Ru(CO)(L)(H) products. Reaction of cis-(CF3PCP)Ru(CO)2Cl with (Et3Si)2(μ-H)+B(C6F5)4− in the presence of excess CO afforded (CF3PCP)Ru(CO)3+. The reaction of CF3PCPH with (PPh3)3Ru(H)(O2CR) (R = Me or Ph) produced the corresponding carboxylate complexes (CF3PCP)Ru(PPh3)(O2CR).