Copper(I)-Catalyzed Regio- and Stereoselective Intramolecular Alkylboration of Propargyl Ethers and Amines
作者:Hiroaki Iwamoto、Yu Ozawa、Koji Kubota、Hajime Ito
DOI:10.1021/acs.joc.7b02071
日期:2017.10.6
transformed into multisubstituted alkenes through stereospecific transformations. Mechanistic studies showed that the chemo- and stereoselectivity of copper(I)-catalyzed borylation depends on the type of leaving group. Density functional theory calculations suggested that the regioselectivity of the borylcupration of the alkyne is controlled by the electronic effect of the oxygen atom of the propargyl ether
C–F Bond Cleavage Enabled Redox-Neutral [4+1] Annulation via C–H Bond Activation
作者:Cheng-Qiang Wang、Lu Ye、Chao Feng、Teck-Peng Loh
DOI:10.1021/jacs.6b12142
日期:2017.2.8
α-difluoromethylene alkyne as a nontraditional one-carbon reaction partner, a synthetically novel method for the construction of isoindolin-1-one derivatives viaRh(III)-catalyzed [4+1] annulation reaction is reported. The 2-fold C-F bondcleavage not only enables the generation of desired product under an overall oxidant-free condition but also results in a net migration of carbon-carbontriplebond. In addition
An Atom-Economical Access to β-Heteroarylated Ketones from Propargylic Alcohols via Tandem Ruthenium/Indium Catalysis
作者:Barry M. Trost、Alexander Breder
DOI:10.1021/ol102706j
日期:2011.2.4
The direct and chemoselective synthesis of β-heteroarylated ketonesfrom secondary propargyl alcohols through tandem Ru/In catalysis is reported. Both electron-rich and neutral heteroarenes, such as furans and indoles, efficiently undergo the redox isomerization/conjugate addition (RICA) sequence to provide the corresponding adducts in yields of up to 97%.
Highly enantioselective addition of linear alkyl alkynes to linear aldehydes
作者:Yuhao Du、Mark Turlington、Xiang Zhou、Lin Pu
DOI:10.1016/j.tetlet.2010.07.082
日期:2010.9
It is discovered that the use of biscyclohexylamine (Cy(2)NH) as an additive can greatly enhance the enantioselectivity for the reaction of linear alkyl alkynes with linear aldehydes. The combination of (S)-BINOL (20 mol %), Cy(2)NH (5 mol %), ZnEt(2) (2 equiv), and Ti(O(i)Pr)(4) (0.5 equiv) catalyzes the reaction at room temperature in diethyl ether solution with 81-89% ee and 57-77% yield. (C) 2010 Elsevier Ltd. All rights reserved.