Syntheses, characterization and facial–meridional isomerism of tungsten tricarbonyl diphosphine complexes
作者:Sodio C. N. Hsu、Wen-Yann Yeh
DOI:10.1039/a704416j
日期:——
fac-[W(CO)3(η2-diphos)(NCMe)] 1–3 [diphos = 1,1′-bis(diphenylphosphino)ferrocene (dppf), dppm (Ph2PCH2PPh2) or dppe (Ph2PCH2CH2PPh2)] with the corresponding diphosphines. The initially afforded facial isomers are converted into the meridional forms (4m–9m) in a subsequent, slow rearrangement process through opening of the chelated diphosphine ligand. A five-co-ordinate, square-pyramidal intermediate is
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.
Substituted metal carbonyls XI. 1,1′-Bis(diphenylphosphino)ferrocene — a bridging, chelating and unidentate ligand in the synthesis of M2(CO)10(μ-PP), M(CO)4(η2-PP) and M(CO)5(η1-PP) (where M = Cr, Mo, W and PP = Fe(C5H4PPh2)2)
作者:T.S.Andy Hor、Lai-Tee Phang
DOI:10.1016/0022-328x(89)85061-2
日期:1989.9
decarbonylation of M(CO)6 (M = Cr, Mo, W) followed by nucleophilic attack by 1,1′-bis(diphenylphosphino)ferrocene (dppf) affords a mixture of heterometallic products which consists mainly of a chelate with a bidentate diphosphine, M(CO)4(dppf), and a dinuclear phosphine-bridged complex M2(CO)10(dppf) at ambient temperature (28° C). The corresponding unidentate diphosphine, M(CO)5(dppf), is obtained
Tungsten Carbyne Complexes Containing 1,1'-Bis(diphenylphosphino)ferrocene (dppf). Reverse Relationship between NMR Chemical Shifts of the Carbyne 13C and the 183W Nuclei and Molecular Structure of WCl(CO)2(dppf)(CPh)
The Fischer-type carbyne complexes containing 1,1'-bis(diphenylphosphino)ferrocene (dppf), WX(CO)2(dppf) (CR) [X = Cl, R = Me, Ph, thienyl, furyl, and ferrocenyl; X = Br; R = ferrocenyl], were synthesized. In these complexes, an increase in the W-183 and a decrease in the carbyne C-13 chemical shifts with increasing pi-donating ability of the carbyne substituents were observed. The ferrocenyl-substituted derivate showed the more enhanced redox potential compared with the corresponding carbonyl analog. The structure of WCl(CO)2(dppf)(CPh) has been determined by the single-crystal X-ray diffraction method. The crystal is monoclinic with space group P2(1)/n, and the cell constants are a = 15.565(3) angstrom, b = 21.493(4) angstrom, c = 11.167(2) angstrom, beta = 92.45(1)degrees, and Z = 4. The structure has been refined to a final R value of 0.052. The coordination geometry around the W atom is octahedral with a cis chelation of dppf. The W-C bond distance [1.82(1) angstrom] is in the normal range. The Cp rings of the dppf ligand in the complex take a staggered conformation, but all the C atoms in each ring are almost coplanar.