Chiral 2-(2-hydroxyaryl)alcohols (HAROLs) with a 1,4-diol scaffold as a new family of ligands and organocatalysts
作者:Ömer Dilek、Mustafa A. Tezeren、Tahir Tilki、Erkan Ertürk
DOI:10.1016/j.tet.2017.11.054
日期:2018.1
Efficient and modular syntheses of chiral 2-(2-hydroxyaryl)alcohols (HAROLs), novel 1,4-diols carrying one phenolic and one alcohol hydroxyl group, have been developed which led to generation of a small library of structurally diverse HAROLs in enantiomerically pure form. Of the different HAROLs examined, a HAROL based on the indan backbone exhibited the highest activity and enantioselectivity in the
高效和模块化的手性2-(2-羟基芳基)醇(HAROLs)的合成,带有一个酚和一个醇羟基的新型1,4-二醇已被开发出来,这导致在对映异构体中生成结构多样的HAROLS小文库纯形式。在考察的不同HAROL中,基于茚满骨架的HAROL在Ti(O i Pr)4(y高达97%, 88%ee)并在三田膦的促进下在Morita-Baylis-Hillman反应中作为氢键供体有机催化剂发挥作用。
Polystyrene-Supported (2<i>S</i>)-(−)-3-<i>exo</i>-Piperazinoisoborneol: An Efficient Catalyst for the Batch and Continuous Flow Production of Enantiopure Alcohols
作者:Laura Osorio-Planes、Carles Rodríguez-Escrich、Miquel A. Pericàs
DOI:10.1021/ol300415f
日期:2012.4.6
(PS-PIB) of 3-exo-morpholinoisoborneol (MIB), designed for increased chemical stability, has been synthesized and used as a ligand in the asymmetric alkylation of aldehydes with Et2Zn. The supportedligand turned out to be highly active and enantioselective for a broad scope of substrates (92–99% ee), allowing repeated recycling. A single-pass, continuousflow process implemented with PS-PIB shows only
Rapid identification of enantioselective ketone reductions using targeted microbial libraries
作者:Michael J Homann、Robert B Vail、Edward Previte、Maria Tamarez、Brian Morgan、David R Dodds、Aleksey Zaks
DOI:10.1016/j.tet.2003.10.123
日期:2004.1
enantioselective reduction of a series of alkyl aryl ketones. Microbial cultures demonstrating utility in reducing model ketones were arrayed in multi-well plates and used to rapidly identify specific organisms capable of producing chiral alcohols used as intermediates in the synthesis of several drug candidates. Approximately 60 cultures were shown to selectively reduce various ketones providing both
调查了大约300个微生物的集合,以通过对映选择性还原一系列烷基芳基酮来生成手性仲醇的能力。将证明在还原模型酮中有用的微生物培养物排列在多孔板中,并用于快速鉴定能够产生手性醇的特定生物,这些手性醇在几种候选药物的合成中用作中间体。显示大约60种培养物可选择性还原提供R和S的各种酮相应醇的对映体含量为92–99%ee,1-4 g / L时产率高达95%。还报道了基于外消旋醇的选择性微生物氧化的手性醇的替代方法。该研究为通过选择性微生物生物转化产生手性醇提供了有用的参考。
Designing New Chiral Ketone Catalysts. Asymmetric Epoxidation of <i>cis</i>-Olefins and Terminal Olefins
作者:Hongqi Tian、Xuegong She、Hongwu Yu、Lianhe Shu、Yian Shi
DOI:10.1021/jo010838k
日期:2002.4.1
class of chiral oxazolidinone ketone catalyst for asymmetric epoxidation. High ee values have been obtained for a number of cyclic and acyclic cis-olefins. The epoxidation was stereospecific with no isomerization observed in the epoxidation of acyclic systems. Encouragingly high ee values have also been obtained for a number of terminalolefins. Mechanistic studies show that electronic interactions play
Enantiomerically pure diamino-bis(tert-thiophene) 1b proved to be a valuable and flexible chiral ligand for Pd- and Zn-catalyzed transformations, allowing for high levels of stereocontrol in asymmetric allylic alkylation (ee up to 99%) and hydrosilylations of prochiral carbonyls (ee up to 97%).