General Asymmetric Hydrogenation of Hetero-aromatic Ketones
摘要:
[GRAPHICS]trans-RuCL2[(R)-xylbinap][(R)-daipen] or the S,S complex acts as an efficient catalyst for asymmetric hydrogenation of hetero-aromatic ketones. The hydrogenation proceeds with a substrate-to-catalyst molar ratio of 1000-40000 to give chiral alcohols in high ee and high yield. The enantioselectivity appears to be little affected by the properties of the hetero-aromatic ring. This method allows for asymmetric synthesis of duloxetine, an inhibitor of serotonin and norepinephrine uptake carriers.
preferentially catalytically. Among all the asymmetric catalytic reactions, asymmetrichydrogenation with H2 (AH) is the most widely used in the industry. With few exceptions, these AH processes usecatalysts based on the three critical metals, rhodium, ruthenium, and iridium. Herein we describe a simple, industrially viable iron catalyst that allows for the AH of ketones, a process currently dominated by ruthenium
手性分子(如醇)对于精细化学品、药物、农用化学品、香料和新型材料的制造至关重要。这些分子需要以高产率和高光学纯度并优先催化生产。在所有的不对称催化反应中,工业上应用最广泛的是与H2(AH)的不对称加氢反应。除了少数例外,这些 AH 工艺使用基于三种关键金属(铑、钌和铱)的催化剂。在本文中,我们描述了一种简单的、工业上可行的铁催化剂,它允许酮的 AH,目前该过程主要由钌和铑催化剂主导。通过将手性 22 元大环配体与廉价、易得的 Fe3(CO)12 结合,多种酮在 50 bar H2 和 45-65 °C 下氢化,提供了非常有价值的手性醇,其对映选择性接近或超过用贵金属催化剂获得的那些。与大多数贵金属催化剂的 AH 相比,铁催化的氢化似乎是非均相的。
Kinetic Resolution of Racemic 1-Heteroarylalkanols by Asymmetric Esterification Using Diphenylacetic Acid with Pivalic Anhydride and a Chiral Acyl-transfer Catalyst
作者:Isamu Shiina、Keisuke Ono、Kenya Nakata
DOI:10.1246/cl.2011.147
日期:2011.2.5
A variety of optically active 1-heteroarylalkanols and their esters, which include heteroaromatic moieties, such as 2-furyl, 2-thienyl, 3-thienyl, 2-thiazoyl, 2-benzothiazoyl, and 2-benzoxazoyl gro...
Copper(I) Hydride-Catalyzed Asymmetric Hydrosilylation of Heteroaromatic Ketones
作者:Bruce H. Lipshutz、Asher Lower、Kevin Noson
DOI:10.1021/ol026755n
日期:2002.11.1
In situ generation of CuH ligated by Takasago's new nonracemic ligand, DTBM-SEGPHOS, leads to an especially reactive reagent capable of effecting asymmetrichydrosilylation of heteroaromatic (H) ketones under very mild conditions. PMHS serves as an inexpensive source of hydride. Substrate-to-ligand ratios on the order of 2000:1 are employed. [reaction: see text]
Microbiological synthesis of variously protected L-glyceraldehydes in high optical purity
作者:Giuseppe Guanti、Luca Banfi、Enrica Narisano
DOI:10.1016/s0040-4039(00)84846-7
日期:1986.1
Variously protected L-glyceraldehydes have been enantioselectively synthesized through a sequence involving acylation of formylanion equivalents with glycolic acid derivatives followed by baker's yeast mediated reduction of the resulting ketones.
Enzymatic Resolution of (<i>R</i>)- and (<i>S</i>)-2-(1-Hydroxyalkyl)thiazoles, Synthetic Equivalents of (<i>R</i>)- and (<i>S</i>)-2-Hydroxy Aldehydes