Synthesis of chromium N-heterocyclic carbene complexes using chromium Fischer carbenes as a source of chromium carbonyls
作者:Seongjin Kim、Soo Young Choi、Young Tak Lee、Kang Hyun Park、Helmut Sitzmann、Young Keun Chung
DOI:10.1016/j.jorganchem.2007.08.043
日期:2007.11
Chromium Fischer carbenecomplexes, [CrOMe(R)}(CO)5] have been utilized as a source of chromium carbonyls in the synthesis of chromium NHC complexes. Using the synthetic method, chromiumcomplexes of various NHC ligands were isolated in reasonable yields. Moreover, the method can be employed for the synthesis of molybdenum and tungsten NHC compounds.
Tin- and Germanium-Substituted Enol Ethers from Fischer Carbene Complexes and Group 14 Vinyl Derivatives
作者:José Barluenga、Rosario González、Francisco J. Fañanás
DOI:10.1021/om9703999
日期:1997.10.1
Trialkyltin- or trialkylgermanium-substituted enol ethers 5 and 2-alkoxy-1,3-butadienes 7 have been prepared by the reaction of Fischer carbene complexes 1−3 and 6 with vinylstannanes and -germanes 4. The opening of the metallacyclobutane intermediate by metalloid migration has been shown by using a 2,2-dideuteriated olefin.
Chemistry of di- and tri-metal complexes with bridging carbene or carbyne ligands. Part 1. Synthesis of platinum–chromium, –molybdenum, and –tungsten compounds; crystal structure of [(OC)<sub>5</sub>W{µ-C(OMe)Ph}Pt(PMe<sub>3</sub>)<sub>2</sub>]
作者:Terence V. Ashworth、Judith A. K. Howard、Mariano Laguna、F. Gordon A. Stone
DOI:10.1039/dt9800001593
日期:——
The compounds [MC(OMe)Ph}(CO)5](M = Cr or W) react with [Pt(cod)2](cod = cyclo-octa-1,5-diene) to give metal—metal-bonded complexes [(OC)5[graphic omitted]t(cod)]. Ethylene-saturated light petroleum solutions of [Pt(cod)2], treated with 2 mol of tertiaryphosphine, react with the mononuclear metal compounds [MC(OMe)Ph}(CO)5](M = Cr, Mo, or W) and [WC(OMe)Me}(CO)5] to afford the carbene-bridged dimetal
Gekkopelte einschiebung von “NC” in die metall-carbenkohlenstoff-bindung und von “C(R′)Ph” in die RCN-bindung bei der reaktion von (CO)5M[C(R′)Ph] mit RCN
作者:Helmut Fischer、Robert Märkl、Siegfried Zeuner
DOI:10.1016/0022-328x(85)87231-4
日期:1985.4
(CO)5M[C(OMe)Ph][M = Cr (Ia), Mo (Ib), W (Ic) react with [(Ph3P)2N][NCBH3] to give the new nitrile complexes [(Ph3P)2N]+ (CO)5M[NCC(OMe)(Ph)BH)3]}−. The reaction of Ic with NCSiMe3 yields (CO)5W[NCC(OMe)(Ph)SiMe3]; however, in the presence of silica gel (CO)5W[NCC(OMe)(Ph)H] is obtained. From the reaction of pentacarbonyl(diphenylcarbene)tungsten, (CO)5W[CPh2], with NCSnBun3 in diethyl ether, (CO)5W[NCCHPh2]
五羰基[甲氧基(苯基)卡宾]络合物(CO)5 M [C(OMe)Ph] [M = Cr(Ia),Mo(Ib),W(Ic)与[(Ph 3 P)2 N]反应[NCBH 3 ],得到新的腈配合物[(PH 3 P)2 N] + (CO)5 M [NCC(OME)(PH)BH)3 ]} - 。Ic的与NCSiMe反应3个产率(CO)5 W [NCC(OME)(PH)森达3 ]; 然而,在硅胶(CO)存在下,得到5 W [N = CC(OMe)(Ph)H]。从五羰基(二苯基碳烯)钨的反应中,(CO)5 W [CPh 2],其中NCSnBu Ñ 3在乙醚中,(CO)5 W [NCCHPh 2 ]分离。从形式上讲,新的腈络合物对应于偶联插入的产物:(a)N ofC从RCN到(CO)5 M [C(R')Ph的MC(R')Ph键中]和(b)的C(R')Ph成RCN的CR键。对于R 3 SiMe
Reactions of Group 6 Fischer carbene complexes with alkynes: effect of the metal on the product distribution and the isolation of a nontautomerized cyclohexadienone complex
作者:William D. Wulff、Brian M. Bax、Timothy A. Brandvold、Kin Shing Chan、Adam M. Gilbert、Richard P. Hsung、John Mitchell、Jon Clardy
DOI:10.1021/om00013a021
日期:1994.1
The first comparative study on the effect of the nature of the metal on the reactions of unsaturated group 6 Fischer carbene complexes with alkynes is reported. The scope of the study includes both aryl- and alkenylcarbene complexes of chromium, molybdenum, and tungsten for both internal and terminal alkynes. Twenty-one different organic structural types have been isolated and characterized from these reactions, but in most instances phenols and indene (cyclopentadiene) products are the two most frequently observed. The general observation made is that phenol formation is favored over indene (cyclopentadiene) formation in the order chromium > tungsten > molybdenum. The effect of the concentration of the alkyne on the distribution between phenol and indene (cyclopentadiene) was also examined and was found to be most prevalent in the order molybdenum > chromium > tungsten. The bis(alkyne)(eta4-cyclohexadienone)molybdenum complex 107 has been isolated in which the final tautomerization to the phenol product has not occurred. This complex has been characterized by X-ray diffraction and provides support for the previous interpretations of the concentration effects for the reactions of chromium complexes. This complex is the first example of the long-proposed ultimate intermediate in these reactions. Crystal data for 107: space group P2(1)/c, Z = 4, a = 19.088(4) angstrom, b = 10.101(1) angstrom c = 14.578(3) angstrom, a = 90.0-degrees, beta = 109.917(13)-degrees, gamma = 90.0-degrees, R = 0.0598, and R(w) = 0.0788 for the 2405 reflections observed.