existing catalytic systems instead generate other N-containing products, e.g., amines, imines and nitriles. Herein, we demonstrate an efficient and selective ruthenium-catalyzed synthesis of primary amides from alcohols and ammonia gas, accompanied by H2 liberation. Various aliphatic and aromatic primary amides were synthesized in high yields, with no observable N-containing byproducts. The selectivity
通过无受体脱氢偶联直接从醇和氨合成广泛使用的伯酰胺是一种非常理想的方法,这代表了一种清洁、原子经济、可持续的过程。然而,这样的反应以前没有被报道过,并且现有的催化系统反而生成其他含氮产物,例如胺、亚胺和腈。在此,我们展示了一种高效、选择性的钌催化的由醇和氨气合成伯酰胺的方法,并伴随着 H 2 的释放。以高产率合成了各种脂肪族和芳香族伯酰胺,没有观察到含氮副产物。该系统对伯酰胺形成的选择性通过密度泛函理论(DFT)计算合理化,这表明半缩醛胺中间体脱氢成伯酰胺比脱水成亚胺更有利。
Unconventional Titania Photocatalysis: Direct Deployment of Carboxylic Acids in Alkylations and Annulations
作者:David W. Manley、Roy T. McBurney、Phillip Miller、Russell F. Howe、Shona Rhydderch、John C. Walton
DOI:10.1021/ja306168h
日期:2012.8.22
Under dry, anaerobic conditions, TiO2 photocatalysis of carboxylic add precursors resulted in carbon-carbon bond-forming processes. High yields of dirners were obtained from TiO2 treatment of carboxylic acids alone: On inclusion of electron-deficient alkenes, efficient alkylations were achieved with methoxymethyl and phenoxymethyl radicals. In reactions with maleic anhydride or maleimides, phenoxyacetic acid produced chromenedione derivatives in addition to adducts. These photocatalytic reactions are simple and cheap to perform, and the TiO2 is easily removed by filtration. The anaerobic photocatalysis strategy offers a range of synthetic possibilities.
US2014/275080
申请人:——
公开号:——
公开(公告)日:——
Blicke; Wright; Zienty, Journal of the American Chemical Society, 1941, vol. 63, p. 2489
作者:Blicke、Wright、Zienty
DOI:——
日期:——
Directed γ-C(sp<sup>3</sup>)–H Alkylation of Carboxylic Acid Derivatives through Visible Light Photoredox Catalysis
作者:Dian-Feng Chen、John C. K. Chu、Tomislav Rovis
DOI:10.1021/jacs.7b09306
日期:2017.10.25
Visible light photoredox catalysis enables direct γ- C(sp3)-H alkylation of saturated aliphatic carbonyl compounds. Electron-deficient alkenes are used as the coupling partners in this reaction. Distinguished site selectivity is controlled by the predominant 1,5-hydrogen atom transfer of an amidyl radical generated in situ.