Competition between insertion and conjugate addition in nickel-catalyzed couplings of enones with unsaturated functional groups
作者:John Montgomery、Jeongbeob Seo、Helen M.P Chui
DOI:10.1016/0040-4039(96)01528-6
日期:1996.9
The intra- and intermolecular couplings of enones with alkynes or enones in the presence of organozincs under Ni(COD)2 catalysis resulted in three general reaction pathways: direct conjugateaddition, cyclization with alkylation, and cyclization with reduction. The effects of substrate structural variations on selectivities among these three pathways were investigated.
CARBOMETALLATION OF ALKYNES AND IMPROVED SYNTHESIS OF UNIQUINONES
申请人:Lipshutz H. Bruce
公开号:US20080086013A1
公开(公告)日:2008-04-10
Methods for the carbometallation of alkynes are presented. Those are useful for the synthesis of CoQ
10
and other ubiquinones as well as for the synthesis of ubiquinol analogs.
Transmetalation reactions of alkenylalanes: copper-catalyzed conjugate addition to enones
作者:Peter Wipf、Jacqueline H. Smitrovich、Choong Woon Moon
DOI:10.1021/jo00037a040
日期:1992.5
An improved synthetic strategy for the in situ preparation of vinyl cuprates from alkynes is presented and used for the stereospecific synthesis of di-, tri-, and tetrasubstituted olefin& Hydroalumination or Cp2ZrCl2-catalyzed carboalumination of alkynes, followed by in situ transmetalation to bis-alkynyl-copper complex [(C4H9C = C)2CuCN]Li2 and addition of enones, led to the isolation of 1,4-addition products in high yields. Stoichiometric or catalytic amounts of copper complex gave similar results. However, in the presence of less than 10 mol % of Cu(I) complex, side products were formed and a significant drop in the yield of the desired conjugate addition product was observed. An ate-transfer mechanism is postulated for the rapid exchange of vinyl ligands from AI(III) to Cu(I) at low temperatures.
[EN] CARBOMETALLATION OF ALKYNES AND IMPROVED SYNTHSIS OF UBIQUINONES<br/>[FR] CARBOMÉTALLATION D'ALCYNES ET SYNTHÈSE AMÉLIORÉE D'UBIQUINONES
申请人:UNIV CALIFORNIA
公开号:WO2008019196A2
公开(公告)日:2008-02-14
[EN] Methods for the carbometallation of alkynes are presented. Those are useful for the synthesis of CoQ10 and other ubiquinones as well as for the synthesis of ubiquinol analogs. [FR] La présente invention concerne des procédés de carbométallation d'alcynes. Ceux-ci se révèlent utiles pour la synthèse de la CoQ10 et d'autres ubiquinones aussi bien que pour la synthèse d'analogues d'ubiquinol.
Enhancing Regiocontrol in Carboaluminations of Terminal Alkynes. Application to the One-Pot Synthesis of Coenzyme Q<sub>10</sub>
作者:Bruce H. Lipshutz、Tom Butler、Asher Lower、Jeff Servesko
DOI:10.1021/ol701469e
日期:2007.9.1
Me(3)Al and Cp(2)ZrCl(2) give rise to an especially effective reagent mix that results in virtually complete control of regiochemistry upon carboalumination of 1-alkynes. One timely application to coenzymeQ10 is highlighted. Regioisomers from subsequent coupling, which would otherwise be very difficult to separate, are avoided.