A RuPHOX−Ru catalyzedasymmetrichydrogenation of γ‐keto acids has been developed, affording the corresponding enantiopure γ‐lactones in high yields and with up to 97% ee. The reaction could be performed on a gram scale with a relatively low catalyst loading (up to 10000 S/C) under the indicated reaction conditions and the resulting products can be transformed to several enantiopure building blocks
已开发出RuPHOX-Ru催化的γ-酮酸不对称氢化反应,可提供高收率和高达97%ee的相应对映体纯γ-内酯。该反应可以在指定的反应条件下以相对较低的催化剂负载量(最高10000 S / C)以克为单位进行,所得产物可以转化为几种对映纯结构单元,生物活性化合物和对映纯药物。
Palladium/Zinc Co‐Catalyzed Asymmetric Hydrogenation of γ‐Keto Carboxylic Acids
作者:Keyang Zhang、Xuexin Zhang、Jingchao Chen、Zixiu Liu、Chunxiang Pan、Yuanbin Zhu、Shiyuan Wu、Baomin Fan
DOI:10.1002/asia.202100244
日期:2021.5.17
A palladium‐catalyzed asymmetric hydrogenation of levulinic acid has been successful developed by using Zn(OTf)2 as co‐catalyst. The present method not only has provided a strategy in the palladium‐catalyzed asymmetric hydrogenation of ketone, but also allowed the preparation of a wide range of chiral γ‐valerolactones in good yields with excellent enantioselectivities.
Catalytic Enantioselective Homoaldol Reactions Using Binol Titanium(IV) Fluoride Catalysts
作者:James L. Gleason、E. Diane Burke、Ngiap Kie Lim
DOI:10.1055/s-2003-37122
日期:——
Titanium (IV) fluoride catalysts, prepared by the combination of (R)-2,2'-binaphthol and TiF 4 , are effective for promoting the homoaldol addition of 1-ethoxy-1-(trimethylsilyloxy)cyclopropane to aldehydes. The reactions proceed with ee's of up to 72% and are effective with a range of aldehyde substrates. The reactions show greatly improved enantioselectivity when compared to those catalyzed by titanium(IV)
Enantioselective Synthesis of γ-Aryl-γ-butyrolactones by Sequential Asymmetric Epoxidation, Ring Expansion, and Baeyer−Villiger Oxidation
作者:Bin Wang、Yu-Mei Shen、Yian Shi
DOI:10.1021/jo061341j
日期:2006.12.1
N-tolyl-substituted oxazolidinone-containing ketone as catalyst and Oxone as oxidant via a sequential asymmetric epoxidation of benzylidenecyclopropanes, ring expansion, and Baeyer−Villigeroxidation. Up to 91% ee was obtained. Optically active cyclobutanones can also be obtained by suppressing the Baeyer−Villigeroxidation with use of more ketone catalyst and less Oxone.
Enantioselective Ketone Hydroacylation Using Noyori’s Transfer Hydrogenation Catalyst
作者:Stephen K. Murphy、Vy M. Dong
DOI:10.1021/ja4021974
日期:2013.4.17
An enantioselectiveketone hydroacylation enables the direct preparation of lactones from keto alcohols. The alcohol is oxidized in situ to an aldehyde, obviating the need to prepare sensitive keto aldehyde substrates. Noyori's asymmetric transferhydrogenationcatalyst was applied to address challenges of reactivity, chemoselectivity, and enantioselectivity.