作者:Abolghasem (Gus) Bakhoda、Quan Jiang、Yosra M. Badiei、Jeffery A. Bertke、Thomas R. Cundari、Timothy H. Warren
DOI:10.1002/anie.201810556
日期:2019.3.11
functionalizing stronger primary and secondary C−H bonds over tertiary and benzylic C−H sites. Herein, we report a Cu catalyst that exhibits a high degree of primary and secondary over tertiary C−H bond selectivity in the amidation of linear and cyclic hydrocarbons with aroyl azides ArC(O)N3. Mechanistic and DFT studies indicate that C−H amidation involves H‐atom abstraction from R‐H substrates by nitrene intermediates
Iron porphyrin catalysed light driven C–H bond amination and alkene aziridination with organic azides
作者:Yi-Dan Du、Cong-Ying Zhou、Wai-Pong To、Hai-Xu Wang、Chi-Ming Che
DOI:10.1039/d0sc00784f
日期:——
strategy for the design of C–N bond formation reactions under mild reaction conditions, the challenge being lack of selectivity as a free nitrene reactive intermediate is usually involved. Herein is described an iron(III) porphyrin catalysed sp3 C–H amination and alkene aziridination with selectivity by using organic azides as the nitrogen source under blue LED light (469 nm) irradiation. The photochemical
Comparative Investigations of Cp*-Based Group 9 Metal-Catalyzed Direct C–H Amination of Benzamides
作者:Travis M. Figg、Sehoon Park、Juhyeon Park、Sukbok Chang、Djamaladdin G. Musaev
DOI:10.1021/om5005868
日期:2014.8.11
Key mechanistic features of the [Cp*MCl2]2 (M = Ir, Rh, Co; all are in group 9) catalyzed C–H amination of benzamides with organic azides were investigated with a strong emphasis on the metal effects on the reaction mechanism, revealing that the Rh- and Ir-catalyzed reactions follow a similar reaction profile, albeit with different individual kinetic and thermodynamic parameters. The observation that
研究了[Cp * MCl 2 ] 2(M = Ir,Rh,Co;均在第9组中)催化的苯甲酰胺与有机叠氮化物的CH-H胺化反应的关键机理,并特别强调了金属对 反应的影响 机理,揭示了Rh和Ir催化的反应遵循相似的反应过程,尽管具有不同的动力学和热力学参数。与铱相比,基于铱的体系在速率和效率方面要优越得多的观察结果归因于铱固有的强相对论效应。钴系统[Cp * Co III ]几乎没有所检查的大多数叠氮化物的催化活性,似乎是[(BA)(Cp *)CoNR] +这些反应的中间产物被表征为具有弱Co-NPh键(“一个电子-两个中心型”)的“ Co(III)-类胡萝卜素自由基”。其Rh和Ir的类似物被表征为具有强M═NR双键的抗磁性金属亚硝酸盐。提供的实验和计算研究表明,反应的限速步骤位于通过协同金属化-去质子化(CMD)机理发生的最后阶段(原金属化)。虽然热力学参数的实验测量与DFT计算非常吻合,但
N-benzoylimido complexes of palladium. Synthesis, structural characterisation and structure–reactivity relationship
作者:Gábor Besenyei、László Párkányi、Gábor Szalontai、Sándor Holly、Imre Pápai、Gábor Keresztury、Andrea Nagy
DOI:10.1039/b403200d
日期:——
= phenyl or substituted phenyl), react with [Pd2Cl2(dppm)2], 1, [dppm = bis(diphenylphosphino)methane] with the formation of novel [Pd2Cl2(μ-NC(O)Ar)(dppm)2], 3, benzoylnitrene complexes that were structurallycharacterised by multinuclear magnetic resonance and IR spectroscopy and, in several instances, by single crystal X-ray diffraction. As shown by crystallographic studies, the C2P4Pd2 rings adopt
The Hofmann and Curtius rearrangements have been widely used in organicsynthesis and developed for the industrial production (5–100 kg) of pharmaceutically relevant amines/amides. However, the existing use of a stoichiometric organicoxidant [(diacetoxyiodo)benzene or trichloroisocyanuric acid for the Hofmann rearrangement] for amides or an activating reagent (diphenylphosphoryl azide for the Curtius
霍夫曼和库尔蒂斯重排已广泛应用于有机合成,并被开发用于医药相关胺/酰胺的工业生产(5-100 kg)。然而,现有的酰胺化学计量有机氧化剂[(二乙酰氧基碘)苯或三氯异氰脲酸用于霍夫曼重排]或羧酸活化剂(二苯基磷酰叠氮化物用于库尔蒂斯重排)对环境不友好且经济上缺乏吸引力。在此,我们报道了酰胺和醛与过酮和卤化物(和NaN 3)的首次绿色氧化,分别生成N-卤代酰胺和酰基叠氮化物,两者重排成常见的异氰酸酯中间体,随后产生稳定的氨基甲酸酯或脲。霍夫曼和库尔蒂斯重排)当被醇或胺捕获时。每次重新安排都有 30 多个示例,证明这种统一的绿色方法非常高效。重要的是,该方法产生无机无毒K 2 SO 4作为唯一的副产物,这比生产化学计量的、有毒的有机碘苯、氯异氰尿酸或二苯基磷酸的现有方法更有优势。值得注意的是,通过这种绿色氧化库尔蒂斯重排,可以从相应的醛有效合成三种尿素基药物和八种手性尿素催化剂。这种用于霍夫曼和