Gas-phase observation and carbon monoxide substitution of cis-Cr(CO)4 (C2H4)2 by time-resolved IR absorption spectrometry
作者:Bruce H. Weiller、Edward R. Grant
DOI:10.1021/ja00238a049
日期:1987.2
Olefin complexes of metal carbonyl fragments have theoretical importance and play a role in numerous catalytic systems. Theory suggests an interesting trend in bond strengths for the bis-olefin and diene complexes of the 16-electron group VI (group 6) carbonyl fragments. Bis-olefin complexes of M(CO)/sub 4/ (M = Cr, Mo, W) are generally thought to be more stable than eta/sup 4/-diene complexes. Experiments
Preparative-scale organometallic chemistry in supercritical fluids; isolation of [Cr(CO)5(C2H4)] as a stable solid at room temperature
作者:James A. Banister、Steven M. Howdle、Martyn Poliakoff
DOI:10.1039/c39930001814
日期:——
A miniature flow reactor has been developed for photochemical reactions in supercritical fluids; [Cr(CO)5(C2H4)] is isolated, for the first time, by the UV photolysis of [Cr(CO)6] in supercritical C2H4 at room temp, with a yield of ca. 40 mg per hour at ca. 80% purity as estimated by IR spectroscopy.
Ethene complexes of chromium; the generation and characterisation of [Cr(CO)5(C2H4)] and cis- and trans-[Cr(CO)4(C2H4)2] and their relative stabilities in liquid xenon solution
作者:Marion F. Gregory、Sarah A. Jackson、Martyn Poliakoff、James J. Turner
DOI:10.1039/c39860001175
日期:——
The unstable complexes [Cr(CO)5(C2H4)] and cis- and trans-[Cr(CO)4(C2H4)2] are generated by photolysis of [Cr(CO)6] in C2H4-doped liquidxenon and are characterised by i.r. spectroscopy; these complexes are all unstable, even at -78 °C with the cis-[Cr(CO)4(C2H4)2] complex being the least stable, decomposing with an enthalpy of activation, ΔH‡, of ∼60 kJ mol–1.
不稳定络合物[Cr(CO)5(C 2 H 4)]和顺式和反式-[Cr(CO)4(C 2 H 4)2 ]是通过在C中光解[Cr(CO)6 ]生成的2 H 4掺杂的液态氙,通过红外光谱进行表征;这些配合物都是不稳定的,即使在-78°C时,顺式-[Cr(CO)4(C 2 H 4)2 ]配合物的稳定性也最差,分解时的活化焓为ΔH ‡约60。千摩尔–1。
Grevels, Friedrich-Wilhelm; Jacke, Juergen; Klotzbuecher, Werner E., Pure and Applied Chemistry, 1988, vol. 60, p. 1017 - 1024
作者:Grevels, Friedrich-Wilhelm、Jacke, Juergen、Klotzbuecher, Werner E.、Oezkar, Saim、Skibbe, Volker
DOI:——
日期:——
Gas-phase organometallic kinetics. 3. The observation and carbon monoxide substitution kinetics of cis-bis(ethene)tetracarbonylchromium by time-resolved infrared absorption spectrometry