Catalysed and uncatalysed substitution reactions of [W(CO)5(NCR)] (R = Me, Et)
作者:Cheryl-Ann Dickson、Anne W. McFarlane、Neil J. Coville
DOI:10.1016/s0020-1693(00)80834-8
日期:1989.4
Abstract The reaction between [W(CO)5(NCR)] (R = Me, Et) and tBuNC in the presence of PdO yielded both [W(CO)4(CNBut)2] and [W(CO)4(NCR)(CNBut)] and revealed that both RCN and CO are catalytically replaced by tBuNC. Reaction of a 2:1 mixture of [W(CO)5(NCMe)] and PPh2(CH2)nPPh2 (P-P; n = 2, 5) in toluene at 55 °C gave a product mixture consisting of the bridged complex [W(CO)5(P-P)W(CO)5] (dominant product)
摘要[W(CO)5(NCR)](R = Me,Et)与tBuNC在PdO存在下的反应产生了[W(CO)4(CNBut)2]和[W(CO)4(NCR) )(CNBut)],并发现RCN和CO均被tBuNC催化取代。[W(CO)5(NCMe)]与PPh2(CH2)nPPh2(PP; n = 2,5)的2:1混合物在甲苯中于55°C反应,得到由桥联配合物[W]组成的产物混合物(CO)5(PP)W(CO)5](主要产物)和螯合物[W(CO)4(PP)]。出乎意料的是,当与PPh2( )nPPh2(n = 4,5)的反应在CHCl3中进行时,螯合物[W(CO)4(PP)]是主要产物。
Ligand substitution kinetics in M(CO)4 (η2:2-1,5-cyclooctadiene) complexes (M=Cr, Mo, W) — substitution of 1,5-cyclooctadiene by bis(diphenylphosphino)alkanes
作者:Ceyhan Kayran、Ferda Kozanoglu、Saim Özkar、Saltuk Saldamlı、Ayşin Tekkaya、Cornelius G. Kreiter
DOI:10.1016/s0020-1693(98)00293-x
日期:1999.1
The thermal substitution kinetics of 1,5-cyclooctadiene (COD) by bis(diphenylphosphino)alkanes (PP), (C6H5)2P(CH2)nP(C6H5)2 (n = 1, 2, 3) in M(CO)4(η2:2-COD) complexes (M = Cr, Mo, W), were studied by quantitative FT-IR spectroscopy. The reaction rate exhibits first-order dependence on the concentration of the starting complex, and the observed rate constant depends on the concentration of the leaving
双(二苯基膦基)烷烃(PP),(C 6 H 5)2 P(CH 2)n P(C 6 H 5)2(n = 1,2 )对1,5-环辛二烯(COD)的热取代动力学,3)在M(CO)4(η2 :2-COD)配合物(M = Cr,Mo,W),通过定量FT-IR光谱法进行了研究。反应速率表现出对起始配合物浓度的一级依赖性,并且观察到的速率常数取决于离开的COD配体的浓度以及进入的PP配体的浓度和性质。在所提出的机理中,速率确定步骤是裂解COD配体的一个金属-烯烃键。从提议的机制中得出了利率定律。动力学数据的评估给出了激活参数,这些参数在过渡态下支持缔合机制。观察到的速率常数和活化参数均显示出随二膦配体的链长的变化很小。
Ligand substitution kinetics in M(CO)4(η2:2-norbornadiene) complexes (M=Cr, Mo, W): displacement of norbornadiene by bis(diphenylphosphino)alkanes
作者:Ayşin Tekkaya、Saim Özkar
DOI:10.1016/s0022-328x(99)00458-1
日期:1999.11
The thermal substitution kinetics of norbornadiene (NBD) by bis(diphenylphosphino)alkanes (PP), (C6H5)2P(CH2)nP(C6H5)2 (n=1, 2, 3) in M(CO)4(η2:2-NBD) complexes (M=Cr, Mo, W), were studied by quantitative FT-IR spectroscopy. The reaction rate exhibits first-order dependence on the concentration of the starting complex, and the observed rate constant depends on the concentration of the leaving NBD ligand
双(二苯基膦基)烷烃(PP),(C 6 H 5)2 P(CH 2)n P(C 6 H 5)2(n = 1,2,3)在水中降冰片二烯(NBD)的热取代动力学M(CO)4(η2 :2-NBD)配合物(M = Cr,Mo,W),通过定量FT-IR光谱研究。反应速率表现出对起始配合物浓度的一级依赖性,观察到的速率常数取决于离去的NBD配体的浓度以及进入的PP配体的浓度和性质。在所提出的机理中,存在两个竞争的初始步骤:涉及进入的PP配体与过渡金属中心的连接的缔合反应和涉及二烯烃配体与过渡金属中心的逐步分离的缔合反应。费率定律是从提出的机制中得出的。活化参数是从动力学数据的评估中获得的。发现在进入配体的浓度较高时,缔合路径占主导地位,而在较低浓度下,解离路径的贡献变得显着。观察到的速率常数和活化参数都显示出随二膦配体的链长的显着变化。
Rapid synthesis of Group VI carbonyl complexes by coupling borohydride catalysis and microwave heating
作者:Kurt R. Birdwhistell、Brian E. Schulz、Paula M. Dizon
DOI:10.1016/j.inoche.2012.09.030
日期:2012.12
tetracarbonyl phosphine and tertiary amine complexes [M(CO)4 L2, M = Cr, Mo, W, L2 = 2PPh3, dppm, dppe, dppp, dppb, bpy, phen, dppf] were synthesized in minutes in the microwave at moderate temperature, atmospheric pressure, and utilizing NaBH4 as a catalyst. The reactions were optimized by careful solvent selection. The octahedral complexes were isolated in percent yields ranging from 17 to 95. The
摘要 在几分钟内合成了几种 VI 族四羰基膦和叔胺配合物 [M(CO)4 L2, M = Cr, Mo, W, L2 = 2PPh3, dppm, dppe, dppp, dppb, bpy, phen, dppf]在中等温度、大气压下进行微波,并利用 NaBH4 作为催化剂。通过仔细选择溶剂来优化反应。八面体配合物以 17 到 95% 的产率被分离出来。与传统的热合成相比,更低的温度、更短的反应时间、温和的溶剂和更低的压力为这些常见的 VI 族配合物提供了一种快速、环保的合成途径.
Lindner, Ekkehard; Fawzi, Riad; Mayer, Hermann August, Organometallics, 1992, vol. 11, # 3, p. 1033 - 1043
作者:Lindner, Ekkehard、Fawzi, Riad、Mayer, Hermann August、Eichele, Klaus、Hiller, Wolfgang