TMAF-Catalyzed Conjugate Addition of Oxazolidinone and Thiols
作者:Vincent Dalla、Mickaël Ménand
DOI:10.1055/s-2004-836057
日期:——
TMAF (Me4NF) is a useful catalyst for the conjugate addition of oxazolidinone and thiols to a range of Michael acceptors including esters, ketones, nitroolefins and cinnamaldehyde.
作者:Yang Yang、Niklas Henrik Fischer、Maria Teresa Oliveira、Gul Barg Hadaf、Jian Liu、Theis Brock-Nannestad、Frederik Diness、Ji-Woong Lee
DOI:10.1039/d2ob00831a
日期:——
Sulphur-selective conjugateaddition reactions play a central role in synthetic chemistry and chemical biology. A general tool for conjugateaddition reactions should provide high selectivity in the presence of competing nucleophilic functional groups, namely nitrogen nucleophiles. We report CO2-mediated chemoselective S-Michael addition reactions where CO2 can reversibly control the reaction pHs,
硫选择性共轭加成反应在合成化学和化学生物学中起着核心作用。共轭加成反应的通用工具应在存在竞争性亲核官能团(即氮亲核试剂)的情况下提供高选择性。我们报告了CO 2介导的化学选择性S-迈克尔加成反应,其中CO 2可以可逆地控制反应pH,从而提供实用的反应条件。硫烷基化产物的化学选择性增加归因于 CO 2作为氮亲核试剂的临时且无痕保护基团,而 CO 2高效地在肽和人血清白蛋白 (HSA) 上提供更高转化率和选择性的硫亲核试剂与各种亲电子试剂。当需要高化学选择性时,该方法为半胱氨酸修饰反应提供了简单的反应条件。
Magnesium‐Catalyzed Asymmetric Thia‐Michael Addition to α,β‐Unsaturated Ketones
作者:Joanna A. Jaszczewska‐Adamczak、Paulina Baczewska、Robert Bujok、Jacek Mlynarski
DOI:10.1002/adsc.202301414
日期:2024.3.19
chiral magnesium complexes in an asymmetric carbon-sulfur bond-forming reaction. Enantioselective and cost-effective methodology under mild condition for the thia-Michael addition, utilizing an in situ generated chiral dinuclear magnesium-ProPhenol complex, has been developed. The versatility of this protocol is demonstrated with a broad range of thiol nucleophiles and a wide selection of enones. Enantioenriched
Asymmetric conjugate addition of thioglycolate to a range of chalcones using tetrahydroisoquinoline (TIQ) N,N′-dioxide ligands
作者:Sai Kumar Chakka、Zamani E.D. Cele、Sphelele C. Sosibo、Vivian Francis、Per I. Arvidsson、Hendrik G. Kruger、Glenn E.M. Maguire、Thavendran Govender
DOI:10.1016/j.tetasy.2012.04.010
日期:2012.4
A series of novel TIQ based N,N'-oxide ligands were synthesised and screened for their catalytic activity in the enantioselective conjugate addition of thioglycolate to chalcones. Bulky groups on the side chain of the TIQ backbone provided the highest enantioselectivity of up to 88% with 10 mol % catalyst loading. It was also observed that these reactions proceeded optimally in the presence of dichloromethane as a solvent. Screening of various metals emphasized La(OTf)(3) as the ideal pre-catalyst for this particular reaction. (C) 2012 Elsevier Ltd. All rights reserved.