Synthesis of Vinyl-, Allyl-, and 2-Boryl Allylboronates via a Highly Selective Copper-Catalyzed Borylation of Propargylic Alcohols
作者:Lujia Mao、Rüdiger Bertermann、Katharina Emmert、Kálmán J. Szabó、Todd B. Marder
DOI:10.1021/acs.orglett.7b03294
日期:2017.12.15
An efficient methodology for the synthesis of vinyl-, allyl-, and (E)-2-boryl allylboronates from propargylic alcohols via Cu-catalyzed borylation under mild conditions is reported. In the presence of commercially available Cu(OAc)2 or Cu(acac)2 and Xantphos, the reaction affords the desired products in up to 92% yield with a broad substrate scope (43 examples). Isolation of an allenyl boronate as
Three different substituted thiazoles have been successfully synthesized from readily available propargylic alcohols. Various secondary propargylic alcohols or tertiary propargylic alcohols participated well in the reaction, providing the desired products in good yields. This method provides a flexible and rapid route to substituted thiazoles.
Lewis Base-Catalyzed Additions of Alkynes Using Trialkoxysilylalkynes
作者:Robert B. Lettan、Karl A. Scheidt
DOI:10.1021/ol051030f
日期:2005.7.1
[reaction: see text]. The Lewis base-catalyzedadditions of alkynyl nucleophiles to aldehydes, ketones, and imines is described. Mechanistic studies strongly indicate that the use of new triethoxysilylalkynes facilitates access of a reactive hypervalent silicate intermediate. This activated carbon nucleophile subsequently undergoes rapid addition to carbonyl compounds and imines, thus affording the
Tetrabutylammonium Fluoride (TBAF)-Catalyzed Addition of Substituted Trialkylsilylalkynes to Aldehydes, Ketones, and Trifluoromethyl Ketones
作者:Venkat Reddy Chintareddy、Kuldeep Wadhwa、John G. Verkade
DOI:10.1021/jo200314g
日期:2011.6.3
efficient catalyst for the addition of trialkylsilylalkynes to aldehydes, ketones, and trifluoromethyl ketones in THF solvent at room temperature. The reaction conditions are mild and operationally simple, and a variety of aryl functional groups, such as chloro, trifluoromethyl, bromo, and fluoro groups, are tolerated. Impressively, using our protocol, useful CF3-bearing tertiary propargylic alcohols
Design and Synthesis of Alanine Triazole Ligands and Application in Promotion of Hydration, Allene Synthesis and Borrowing Hydrogen Reactions
作者:Yongchun Yang、Anni Qin、Keyan Zhao、Dawei Wang、Xiaodong Shi
DOI:10.1002/adsc.201600141
日期:2016.4.28
alanine triazole (ATA) ligand was found to be an efficient partner for the stabilization of gold(III), thus rendering improved stability and high catalytic activities in allene synthesis and hydration reactions through the 3,3′‐arrangement of propargyl esters and propargyl alcohols. In addition to Au(I), ATA‐gold(III) was also proven to be an effective catalyst in promoting the formation of allenes