Kinetic resolution of heteroaryl β-hydroxy sulfides catalyzed by Humicola lanuginosa lipase
摘要:
Humicola lanuginosa lipase-catalyzed resolution of heteroaryl substituted beta-hydroxy sulfides by irreversible transesterification using vinyl acetate as acylating agent is discussed. The ee of the resolved alcohols was determined from the H-1 NMR of their corresponding (S)-(+)-O-acetylmandelic acid esters. (C) 2002 Elsevier Science Ltd. All rights reserved.
Effects of adjacent acceptors and donors on the stabilities of carbon-centered radicals
作者:F. G. Bordwell、Xianman Zhang、Mikhail S. Alnajjar
DOI:10.1021/ja00046a003
日期:1992.9
the electron-withdrawing effect of the group is large, as in Fsub 3}Csup sm_bullet}} and Mesub 3}Nsup +}CHsub2}sup sm_bullet}} radicals, the net effect is to destabilize the radical relative to the methyl radical. The RSEs of 12 radicals of the type RSCsup sm_bullet}}HG or PhSCsup sm_bullet}}HG, relative to that of the GCHsub2}sup sm_bullet}} radical, were foundmore » to increase progressively
Catalyst-Free Insertion of Sulfoxonium Ylides into Aryl Thiols. A Direct Preparation of β-Keto Thioethers
作者:Rafael M. P. Dias、Antonio C. B. Burtoloso
DOI:10.1021/acs.orglett.6b01470
日期:2016.6.17
Insertion of sulfoxoniumylides into the S–H bond of aryl thiols without the need for a catalyst is demonstrated, furnishing β-keto thioethers in excellent yield in most cases. The method overcomes traditional syntheses that employ metal catalysts in combination with diazo compounds or toxic and hard-prepared haloketones. The experimental setup consists of mixing the reagents in acetonitrile at room
Cooperative Photoinduced/Brønsted Acid Catalyzed Cycloaddition of Transient Thioaldehydes and <i>ortho</i>-Quinone Methides toward a Synthesis of Benzo[<i>e</i>][1,3]oxathiines
作者:Florian Sachse、Christoph Schneider
DOI:10.1021/acs.orglett.1c00588
日期:2021.4.2
in situ generation and ensuing cycloaddition of thioaldehydes and ortho-quinone methides transiently formed under irradiation with UV-A light and Brønsted acid catalysis, respectively, has been developed giving direct access to benzo[e][1,3]oxathiines in good to excellent yields and diastereoselectivity. Both electron-rich and electron-poor thioaldehydes easily react with a broad range of ortho-quinone
已经开发了一种合作的一锅法,用于原位生成并随后分别在UV-A光和Brønsted酸催化下短暂形成的硫代醛和邻醌甲基化物环加成反应,从而可以直接获得苯并[ e ] [ 1,3]氧杂蒽酮具有良好的收率和非对映选择性。富电子和贫电子的硫醛都可以在环境温度下以很短的反应时间轻松地与各种邻苯二甲基甲烷反应,以提供各种S,O-杂环。
The thiol-sulfoxonium ylide photo-click reaction for bioconjugation