Alkyne Competition in the Benzannulation Reaction with Chromium Carbene Complexes
作者:Chunrui Wu、Dmytro O. Berbasov、William D. Wulff
DOI:10.1021/jo100433k
日期:2010.7.2
The benzannulation reaction of Fischer carbenecomplexes is investigated under conditions where the reaction of the carbenecomplex is occurring in the presence of two different alkynes. A series of competition experiments are examined where the effects of various structural factors are explored by pitting 10 different carbenecomplexes with 11 different alkynes. Terminal alkynes will react selectively
The development of an organotransition metal synthesis of quinones
作者:Lenny S. Liebeskind、Sherrol L. Baysdon、Michael S. South、Suresh Iyer、James P. Leeds
DOI:10.1016/s0040-4020(01)91423-1
日期:1985.1
A new and very general synthesis of quinones is described from conception to the current state of maturity. The chemistry relies on a convergent joining of a transition metalcomplex and an alkyne to provide benzoquinones (from maleoylmetal complexes) and naphthoquinones (from phthaloylmetal complexes). Significant aspects of this chemistry are its generality (terminal, internal, electron rich, and
Solvent, chelation and concentration effects on the benzannulation reaction of chromium carbene complexes and acetylenes
作者:Kin Shing Chan、Glen A. Peterson、Timothy A. Brandvold、Katherine L. Faron、Cynthia A. Challener、Carol Hyldahl、William D. Wulff
DOI:10.1016/0022-328x(87)80037-2
日期:1987.11
in solvent or substituents on the acetylene. The reactions of aryl complexes with acetylenes are quite sensitive to the nature of the solvent and the acetylene. The highest selectivities and efficiencies for the benzannulated product from the reactions of aryl complexes are with solvents of low coordinating ability. Solvents with intermediate coordinating ability and small size give high selectivity
Benzannulation of .alpha.,.beta.-unsaturated Fischer carbene complexes with acetylenes
作者:William D. Wulff、Kin Shing Chan、Peng Cho Tang
DOI:10.1021/jo00186a046
日期:1984.6
Approaching ambient temperatures in 1,2-DCE to deliver efficient intermolecular Dötz benzannulation processes
作者:Stephanie Irvine、William J. Kerr、Allan R. McPherson、Colin M. Pearson
DOI:10.1016/j.tet.2007.09.088
日期:2008.1
Conditions have been developed that enable intermolecular Dotz benzannulations to be carried out under extremely mild conditions, using 1,2-DCE as the reaction solvent and without the requirement for any additional reaction promoters. The new protocols, at temperatures close to ambient, have been applied successfully to a range of internal and terminal alkynes with a series of aryl and alkenyl carbene complexes, resulting in good to high yields of the benzannulation products. The developed conditions did, however, return lower benzannulation yields when utilised with the traditionally more troublesome 2-furyl carbene complex. It was found that increased reaction temperatures in 1,2-DCE did deliver high yields for the processes with this heteroaryl species. (c) 2007 Elsevier Ltd. All rights reserved.