25086-42-4Relevant articles and documents
Method for preparing amine through catalytic reduction of nitro compound by cyclic (alkyl) (amino) carbene chromium complex
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Paragraph 0015, (2021/04/17)
The cyclic (alkyl) (amino) carbene chromium complex is prepared from corresponding ligand salt, alkali and CrCl3 and used for catalyzing pinacol borane to reduce nitro compounds in an ether solvent under mild conditions to generate corresponding amine. The method for preparing amine has the advantages of cheap and accessible raw materials, mild reaction conditions, wide substrate application range, high selectivity and the like, and is simple to operate.
Cyclic (Alkyl)(amino)carbene Ligand-Promoted Nitro Deoxygenative Hydroboration with Chromium Catalysis: Scope, Mechanism, and Applications
Zhao, Lixing,Hu, Chenyang,Cong, Xuefeng,Deng, Gongda,Liu, Liu Leo,Luo, Meiming,Zeng, Xiaoming
supporting information, p. 1618 - 1629 (2021/01/25)
Transition metal catalysis that utilizes N-heterocyclic carbenes as noninnocent ligands in promoting transformations has not been well studied. We report here a cyclic (alkyl)(amino)carbene (CAAC) ligand-promoted nitro deoxygenative hydroboration with cost-effective chromium catalysis. Using 1 mol % of CAAC-Cr precatalyst, the addition of HBpin to nitro scaffolds leads to deoxygenation, allowing for the retention of various reducible functionalities and the compatibility of sensitive groups toward hydroboration, thereby providing a mild, chemoselective, and facile strategy to form anilines, as well as heteroaryl and aliphatic amine derivatives, with broad scope and particularly high turnover numbers (up to 1.8 × 106). Mechanistic studies, based on theoretical calculations, indicate that the CAAC ligand plays an important role in promoting polarity reversal of hydride of HBpin; it serves as an H-shuttle to facilitate deoxygenative hydroboration. The preparation of several commercially available pharmaceuticals by means of this strategy highlights its potential application in medicinal chemistry.
Boosting chemoselective reduction of 4-nitrostyreneviaphotoinduced energetic electrons fromin situformed Cu nanoparticles on carbon dots
Ren, Yuqi,Hao, Caihong,Chang, Qing,Li, Ning,Yang, Jinlong,Hu, Shengliang
supporting information, p. 2938 - 2943 (2021/05/05)
Chemoselective hydrogenation of structurally diverse nitroarenes is a challenging process that often requires precious metal catalysts and proceeds in an organic solvent. Herein, a convenient and stable hybrid nanocatalyst combining carbon dots and copper nanoparticles is developed as an ideal alternative for this transformation. The as-prepared nanocatalyst achieves over 99% selectivity for the formation of 4-aminostyrene at 100% conversion of 4-nitrostyrene in an aqueous solvent under visible light irradiation. Compared with other reported catalysts, our presented catalyst shows more superior hydrogenation selectivity and stability as well as lower material cost. This high efficiency could be originated from the nanocatalyst's ability to synergistically control surface hydrogen species released from ammonia borane and energetic “hot” electrons induced by visible light irradiation for the selective reduction reaction. Compared with other reported catalysts, our presented nanocatalyst is better for the realization of energy-saving chemical processes by introducing solar energy.