A facile asymmetric transfer hydrogenation of ortho-substituted aryl N-heteroaryl ketones and non-ortho-substituted N-oxide of aryl N-heteroaryl ketones using a readily available oxo-tethered ruthenium complex as a catalyst and sodium formate as a hydrogen source in an aqueous solution has been discovered. A variety of chiral aryl N-heteroaryl methanols were obtained with up to 99.9% ee.
Photoenzymatic Hydrogenation of Heteroaromatic Olefins Using ‘Ene’‐Reductases with Photoredox Catalysts
作者:Yuji Nakano、Michael J. Black、Andrew J. Meichan、Braddock A. Sandoval、Megan M. Chung、Kyle F. Biegasiewicz、Tianyu Zhu、Todd K. Hyster
DOI:10.1002/anie.202003125
日期:2020.6.22
selective catalysts for the asymmetric reduction of activated alkenes. This function is, however, limited to enones, enoates, and nitroalkenes using the native hydride transfer mechanism. Here we demonstrate that EREDs can reduce vinyl pyridines when irradiated with visible light in the presence of a photoredoxcatalyst. Experimental evidence suggests the reaction proceeds via a radical mechanism where
Iridium-Catalyzed Highly Enantioselective Transfer Hydrogenation of Aryl <i>N</i>-Heteroaryl Ketones with <i>N</i>-Oxide as a Removable <i>ortho</i>-Substituent
作者:Qixing Liu、Chunqin Wang、Haifeng Zhou、Baigui Wang、Jinliang Lv、Lu Cao、Yigang Fu
DOI:10.1021/acs.orglett.7b03878
日期:2018.2.16
A highlyenantioselectivetransferhydrogenation of non-ortho-substituted aryl N-heteroaryl ketones, using readily available chiral diamine-derived iridium complex (S,S)-1f as a catalyst and sodium formate as a hydrogen source in a mixture of H2O/i-PrOH (v/v = 1:1) under ambient conditions, is described. The chiral aryl N-heteroaryl methanols were obtained with up to 98.2% ee by introducing an N-oxide
使用容易获得的手性二胺衍生的铱络合物(S,S)-1f作为催化剂,甲酸钠作为氢源的H 2 O混合物,对非邻位取代的芳基N-杂芳基酮进行高度对映选择性转移氢化/我的i-PrOH(v / v = 1:1)在环境条件下,进行说明。通过引入N-氧化物作为可除去的邻位取代基,获得具有高达98.2%ee的手性芳基N-杂芳基甲醇。相反,在不存在氮的情况下,观察到的ee不超过15.1%-氧化物部分。此外,该协议的实用性还通过克规模的苯磺酸他莫司汀的克级不对称合成以51%的总收率和99.9%的ee进行了证明。
A convenient and practical heterogeneous palladium‐catalyzed carbonylative Suzuki coupling of aryl iodides with formic acid as carbon monoxide source
作者:Shengyong You、Chenyu Yan、Rongli Zhang、Mingzhong Cai
DOI:10.1002/aoc.4650
日期:——
palladium‐catalyzed carbonylative Suzuki coupling of aryl iodides with arylboronic acids under carbonmonoxide gas‐free conditions has been developed using a bidentate phosphino‐functionalized magnetic nanoparticle‐immobilized palladium(II) complex as catalyst. Formic acid was utilized as the carbonmonoxide source with dicyclohexylcarbodiimide as the activator, and a wide variety of biaryl ketones were
A copper/iodine cocatalyzed decarboxylative cyclization of α-amino acids is described. Starting from the readily available amino acids and either 2-benzoylpyridines or 2-benzoylquinolines, 1,3-disubstituted imidazo[1,5-a]pyridines and 1,3-disubstituted imidazo[1,5-a]quinolines were prepared in excellent yields.
描述了铜/碘共催化的α-氨基酸的脱羧环化。从容易获得的氨基酸和2-苯甲酰基吡啶或2-苯甲酰基喹啉开始,以优异的条件制备了1,3-二取代的咪唑并[1,5- a ]吡啶和1,3-二取代的咪唑并[1,5- a ]喹啉产量。