Rhodium(III)-Catalyzed Directed C−H Amidation of <i>N</i>
-Nitrosoanilines and Subsequent Formation of 1,2-Disubstituted Benzimidazoles
作者:Yanyu Chen、Rong Zhang、Qiujun Peng、Lanting Xu、XianHua Pan
DOI:10.1002/asia.201701287
日期:2017.11.2
An efficient rhodium‐catalyzeddirectC−Hamidation of N‐nitrosoanilines with 1,4,2‐dioxazol‐5‐ones as amidating agents has been developed. This method featured mild reaction conditions, a wide substrate scope and satisfactory yields. Besides, the amidated products could be readily converted to pharmaceutically valuable 1,2‐disubstituted benzimidazoles via an HCl‐mediated deprotection/cyclization process
Silver-catalyzed regioselective deuteration of (hetero)arenes and α-deuteration of 2-alkyl azaarenes
作者:Baobiao Dong、Xuefeng Cong、Na Hao
DOI:10.1039/d0ra02358b
日期:——
A simple silver-catalyzed regioselective deuteration of (hetero)arenes and α-deuteration of 2-alkyl azaarenes has been described. This strategy provides an efficient and practical avenue to access various deuterated electron-rich arenes, azaarenes and α-deuterated 2-alkyl azaarenes with good to excellent deuterium incorporation utilizing D2O as the source of deuterium atoms.
已经描述了(杂)芳烃的简单银催化区域选择性氘化和 2-烷基氮杂芳烃的 α-氘化。该策略为利用 D 2 O 作为氘原子源获得各种氘代富电子芳烃、氮杂芳烃和 α-氘代 2-烷基氮杂芳烃提供了一种有效且实用的途径,这些氘代具有良好的氘掺入能力。
A Versatile, Traceless C–H Activation-Based Approach for the Synthesis of Heterocycles
A versatile, traceless C–H activation-based approach for the synthesis of diversified heterocycles is reported. Rh(III)-catalyzed, N-amino-directed C–H alkenylation generates either olefination products or indoles (in situ annulation) in an atom- and step-economic manner at room temperature. The remarkable reactivity endowed by this directing group enables scale-up of the reaction to a 10 g scale at
A highly effective and operationally practical method for the regioselectivedeuteration of N-alkyl-substituted anilines employing Ru3(CO)12 (⩽1 mol %) as catalyst and D2O as deuterium source was described. A variety of N-alkyl-substituted anilines were efficiently deuterated (up to 98%) at the ortho and/or para position with respect to the nitrogen at neutral conditions. Under the present conditions
Synthesis of Symmetric Bis(<i>N</i>-alkylaniline)triarylmethanes via Friedel–Crafts-Catalyzed Reaction between Secondary Anilines and Aldehydes
作者:Rafael F. A. Gomes、Jaime A. S. Coelho、Raquel F. M. Frade、Alexandre F. Trindade、Carlos A. M. Afonso
DOI:10.1021/acs.joc.5b01875
日期:2015.10.16
The first general protocol for the preparation of symmetric triarylmethanes bearing secondary anilines by ytterbium-catalyzed Friedel–Crafts reaction of hetero(aryl) aldehydes and secondary anilines is reported. Mechanistic studies indicated that the iminium ion intermediate is the electrophilic partner. The reaction is greatly accelerated by high pressure (9 kbar) and showed a broad substrate scope