Indium metal as a reducing agent in organic synthesis
作者:Michael R. Pitts、Justin R. Harrison、Christopher J. Moody
DOI:10.1039/b101712h
日期:——
aromatic nitrocompounds under similar conditions results in selectivereduction of the nitro groups; ester, nitrile, amide and halide substituents are unaffected. Likewise indium in aqueous ethanolic ammonium chloride is an effective method for the deprotection of 4-nitrobenzyl ethers and esters. Indium is also an effective reducing agent under non-aqueous conditions and α-oximino carbonyl compounds can
作者:Yan Wang、Baobiao Dong、Zikun Wang、Xuefeng Cong、Xihe Bi
DOI:10.1021/acs.orglett.9b01055
日期:2019.5.17
A ligand- and base-free silver-catalyzed reduction of quinolines and electron-deficient aromatic N-heteroarenes in water has been described. Mechanistic studies revealed that the effective reducing species was Ag–H. This versatile catalytic protocol provided facile, environmentally friendly, and practical access to a variety of 1,2,3,4-tetrahydroquinoline derivatives at room temperature.
A rapid and efficient method for the reduction of quinoxalines
作者:Andrew M. McKinney、Kevin R. Jackson、Ralph Nicholas Salvatore、Elena-Maria Savrides、Mary Jane Edattel、Terrence Gavin
DOI:10.1002/jhet.5570420546
日期:2005.7
Mono and di-substituted alkyl and aryl quinoxalines are rapidly reduced in high yield to their respective 1,2,3,4-tetrahydro-derivatives by borane in THF solution. In the case of the 2,3-di-substituted compounds, reduction is stereoselective yielding exclusively the cis-isomers. Sodium borohydride in acetic acid also reduces alkyl and aryl quinoxalines, but proceeds with lower yields and often produces
Transfer hydrogenation of unsaturated nitrogen heterocycles using a rhodiumcatalyst immobilized on bipyridine-periodic mesoporous organosilica (BPy-PMO) is described. The immobilized catalyst was prepared by mixing [Cp*RhCl2]2 (Cp* = η5-C5Me5) with BPy-PMO powder in DMF at 60 °C and characterized by nitrogen adsorption measurements, solid-state NMR spectroscopy, X-ray diffraction, energy-dispersive
Asymmetric Transfer Hydrogenations of 2,3-Disubstituted Quinoxalines with Ammonia Borane
作者:Songlei Li、Wei Meng、Haifeng Du
DOI:10.1021/acs.orglett.7b00935
日期:2017.5.19
An asymmetrictransferhydrogenation of 2,3-disubstituted quinoxalines using a chiral frustrated Lewis pair of Piers’ borane and (R)-tert-butylsulfinamide as the catalyst with ammoniaborane as the hydrogen source has been successfully realized. For 2-alkyl-3-arylquinoxaline substrates, cis-tetrahydroquinoxalines were obtained as the predominant products in high yields with 77–86% ee. In contrast,