介绍了一系列新型有机催化剂的设计、制备和研究。催化剂的设计灵感来自于 DNA 核碱基发展精确和明确的氢键的能力。我们已经表明,这种现象可用于创建一种有用的有机催化剂,该催化剂显示出类似于常见有机底物的识别模式。基于鸟嘌呤结构的选定双功能催化剂已被证明可催化 1,3-二羰基化合物与各种硝基烯烃的共轭加成,从而以良好的产率和对映选择性提供产品。
of hybrid catalysts incorporating chloramphenicol base with another chiral scaffold using a squaramide linker have been developed and successfully applied in Michael addition of 2,3-dihydrobenzofuran-2-carboxylates to nitroolefins. The controlling experiments suggested that the hybrid catalysts were more reactive than non-hybridized bifunctional catalysts and the matching of chiralities between two
Highly Diastereo- and Enantioselective Organocatalytic One-Pot Sequential 1,4-Addition/Dearomative-Fluorination Transformation
作者:Feng Li、Long Sun、Yuou Teng、Peng Yu、John Cong-Gui Zhao、Jun-An Ma
DOI:10.1002/chem.201202636
日期:2012.11.5
Fluorination: A wide range of nitroolefins and pyrazol‐5‐ones undergo a sequential 1,4‐addition/dearomative‐fluorination transformation when treated with a catalytic amount of a tertiary‐amine—thiourea compound and the terminal electrophile, N‐fluorobenzenesulfonimide, to give fluorinated products in 72–95 % yield with up to 99:1 d.r. and 98 % ee. Notably, these products contain adjacent tertiary and
Highly Diastereo- and Enantioselective Michael Additions of 3-Substituted Oxindoles to Maleimides Catalyzed by Chiral Bifunctional Thiourea−Tertiary Amine
A highlydiastereo- and enantioselective Michael addition reaction with respect to prochiral 3-substituted oxindoles and maleimides by a chiral bifunctional thiourea−tertiary amine catalyst was investigated for the first time. The corresponding adducts, containing a quaternary center at the C3-position of the oxindole as well as a vicinal tertiary center, were generally obtained in good to high yields
α-disubstituted α-amino acid is a valuable structural motif for research in the field of bioorganic chemistry and in the development of peptide drugs. This report describes the enantioselective direct-aldol reaction of α-iminoesters with glyoxylate esters. We discovered that a catalytic amount of Co(OAc)2-pybox complex catalyzed the aldol reaction of salicylaldehyde-derived α-iminoesters with benzyl glyoxylate
Highly Enantioselective Iridium-Catalyzed Hydrogenation of <i>o</i>-Amidophenyl Ketones Enabled by 1,2-Diphenylethylenediamine-Derived P,N,N-Ligands with Tertiary Amine Terminus
作者:Yin-Bo Wan、Xiang-Ping Hu
DOI:10.1021/acs.orglett.2c02316
日期:2022.8.12
A readily available and highly modular class of chiral P,N,N-ligands based on a structurally flexible nonchiral phosphine-amine framework with an opticallyactive 1,2-diphenylethylenediamine unit bearing a tertiary amine terminus as the chiral source have been developed and successfully applied in the Ir-catalyzed asymmetrichydrogenation of o-amidophenyl ketones. These tridentate P,N,N-ligands exhibited