Direct Conjugate Addition of Alkynes with α,β-Unsaturated Carbonyl Compounds Catalyzed by NCN-Pincer Ru Complexes
作者:Jun-ichi Ito、Kohei Fujii、Hisao Nishiyama
DOI:10.1002/chem.201203380
日期:2013.1.7
the direct conjugate additions of α,β‐unsaturatedcarbonylcompounds, including ketones, esters, and amides, as well as vinylphosphonates, giving various β‐alkynyl carbonyl and phosphonate compounds. A bis(oxazolinyl)phenyl (phebox)–Ru complex also catalyzes the asymmetric conjugate addition of an alkyne with a β‐substituted, α,β‐unsaturated ketone to produce a chiral β‐alkynyl ketone.
opening/alkynylation of cyclopropanol by employing inexpensive and commercially available terminal alkyne is developed. The reactions proceeded efficiently to afford synthetically useful alk-4-yn-1-ones in moderate to good yields with good functional group tolerance. Control experiments showed that the reaction presumably proceeds via the formation of intermediates of copper homoenolate and/or alkynylcopper
The addition of terminal alkynes to acrylate esters in the presence of a ruthenium catalyst and chloride sources proceeds to give the corresponding γ,δ-alkynyl esters in good yields.
with alkyl acrylates proceeds in the presence of a catalytic amount of Ru3(CO)12 and lithium iodide to give the corresponding conjugate dienes. These two different types of catalytic carbon-carbon bondforming reactions are controlled only by the nature of halide ions, either a chloride or an iodide, with other conditions being kept almost the same.
Indium(III) Chloride Catalyzed Conjugate Addition Reaction of Alkynylsilanes to Acrylate Esters
作者:Yan-li Xu、Ying-ming Pan、Pei Liu、Heng-shan Wang、Xiao-yan Tian、Gui-fa Su
DOI:10.1021/jo202628c
日期:2012.4.6
A novel and efficient procedure for the synthesis of δ,γ-alkynyl esters by the conjugateaddition of alkynylsilanes to acrylate esters in the presence of a catalytic amount of indium(III) chloride has been developed. This method provides a rapid and efficient access to substituted δ,γ-alkynyl esters.