119619-37-3Relevant articles and documents
Chiral-at-metal iridium complex for efficient enantioselective transfer hydrogenation of ketones
Tian, Cheng,Gong, Lei,Meggers, Eric
, p. 4207 - 4210 (2016)
A bis-cyclometalated iridium(iii) complex with metal-centered chirality catalyzes the enantioselective transfer hydrogenation of ketones with high enantioselectivities at low catalyst loadings down to 0.002 mol%. Importantly, the rate of catalysis and enantioselectivity are markedly improved in the presence of a pyrazole co-ligand. The reaction is proposed to proceed via an iridium-hydride intermediate exploiting metal-ligand cooperativity (bifunctional catalysis).
Optically active 1-(benzofuran-2-yl)ethanols and ethane-1,2-diols by enantiotopic selective bioreductions
Paizs, Csaba,Tosa, Monica,Majdik, Cornelia,Moldovan, Paula,Novak, Lajos,Kolonits, Pal,Marcovici, Adriana,Irimie, Florin-Dan,Poppe, Laszlo
, p. 1495 - 1501 (2003)
Enantiotopic selective reduction of 1-(benzofuran-2-yl)ethanones 1a-d, 1-(benzofuran-2-yl)-2-hydroxyethanones 4a-c and 2-acetoxy-1-(benzofuran-2-yl)ethanones 3a-c was performed by baker's yeast for preparation of optically active (benzofuran-2-yl)carbinols [(S)-5a-d, (S)-6a-c and (R)-6a-c, enantiomeric excess from 55 to 93% ee].
Reductive 3-Silylation of Benzofuran Derivatives via Coupling Reaction with Chlorotrialkylsilane
Zheng, Suhua,Zhang, Tianyuan,Maekawa, Hirofumi
, p. 13965 - 13972 (2020)
Reductive silylation of benzofurans with an electron-withdrawing group by a magnesium metal and the subsequent oxidative rearomatization by DDQ gave the selective formation of less reported 3-silylated benzofurans in moderate to good yields under mild reaction conditions with wide substituent scope. The silyl group introduced on the five-membered ring by the reductive coupling could survive with no elimination throughout the oxidation process. The silylated heteroaromatic skeleton is useful as an intermediate in organic synthesis, and its practical utility was also demonstrated by several transformation reactions.
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Elliott
, p. 754 (1951)
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Enantioselectivity of some 1-(benzofuran-2-yl)-1-(1-H-imidazol-1-yl) alkanes as inhibitors of P450(Arom)
Khodarahmi, G. Ali,Smith, H. John,Nicholls, Paul J.,Ahmadi, Masoud
, p. 1321 - 1330 (1998)
The low stereospecificity of the enantiomers of 1-[(benzofuran-2-yl)-4-chlorophenylmethyl]imidazole (6, R = H, R' = 4'-Cl) and the corresponding 4-fluoro compound as inhibitors of aromatase (P450(Arom)) has been explored using 1-(5,7-dichlorobenzofuran-2-yl)-1-(1H-imidaz-1-yl)ethane (7, R1 = R2 = Cl, R = CH3), -propane (7, R1 = R2 = Cl, R = C2H5), and the corresponding 5,7-dibromo compounds resolved as their dibenzoyl-D (or -L) tartrates. Low enantioselectivity ratios of 4.8 (5,7-diCl) and 12.6 (5,7-diBr) were shown for the ethanes. The values for the corresponding propanes were 8.3 and 5.2, respectively, and for these compounds the stereoselectivity was reversed.
Asymmetric reduction of aromatic heterocyclic ketones with bio-based catalyst Lactobacillus kefiri P2
Bayda?, Yasemin,Kalay, Erbay,?ahin, Engin
, p. 1147 - 1155 (2020/10/06)
Abstract: Chiral heterocyclic secondary alcohols have received much attention due to their widespread use in pharmaceutical intermediates. In this study, Lactobacillus kefiri P2 biocatalysts isolated from traditional dairy products, were used to catalyze the asymmetric reduction of prochiral ketones to chiral secondary alcohols. Secondary chiral carbinols were obtained by asymmetric bioreduction of different prochiral substrates with results up to > 99% enantiomeric excess (ee). (R)-1-(benzofuran-2-yl)ethanol 5a, which can be used in the synthesis of pharmaceuticals such as bufuralols potent nonselective β-blockers antagonists, Amiodarone (cardiac anti-arrhythmic), and Benziodarone (coronary vasodilator), was produced in gram-scale, high yield and enantiomerically pure form using L. kefiri P2 biocatalysts. The gram-scale production was carried out, and 9.70?g of (R)-5a in enantiomerically pure form was obtained in 96% yield. Also, production of (R)-5a in terms of yield and gram scale through catalytic asymmetric reduction using the biocatalyst was the highest report so far. This is a cost-effective, clean and eco-friendly process for the preparation of chiral secondary alcohols compared to chemical processes. From an environmental and economic perspective, this biocatalytic method has great application potential, making it a green and sustainable way of synthesis. Graphical Abstract: [Figure not available: see fulltext.]
Zinc Hydride-Catalyzed Hydrofuntionalization of Ketones
Sahoo, Rajata Kumar,Mahato, Mamata,Jana, Achintya,Nembenna, Sharanappa
, p. 11200 - 11210 (2020/10/12)
Three new dimeric bis-guanidinate zinc(II) alkyl, halide, and hydride complexes [LZnEt]2 (1), [LZnI]2 (2) and [LZnH]2 (3) were prepared. Compound 3 was successfully employed for the hydrosilylation and hydroboration of a vast number of ketones. The catalytic performance of 3 in the hydroboration of acetophenone exhibits a turnover frequency, reaching up to 5800 h-1, outperforming that of reported zinc hydride catalysts. Notably, both intra- and intermolecular chemoselective hydrosilylation and hydroboration reactions have been investigated.
