Direct Carbo-Acylation Reactions of 2-Arylpyridines with α-Diketones via Pd-Catalyzed C–H Activation and Selective C(sp2)–C(sp2) Cleavage
摘要:
An efficient carbo-acylation reaction of 2-arylpyridines with alpha-diketones via Pd-catalyzed C-H bond activation and C-C bond cleavage in the presence of TBHP was developed that generated aryl ketones in good yields. The highly selective formation of aryl ketones was observed when 2-arylpyridines reacted with aromatic/aliphatic alpha-diketones.
Manganese-Catalyzed Direct Nucleophilic C(sp<sup>2</sup>)H Addition to Aldehydes and Nitriles
作者:Bingwei Zhou、Yuanyuan Hu、Congyang Wang
DOI:10.1002/anie.201506187
日期:2015.11.9
Herein, a manganese‐catalyzed nucleophilicaddition of inert C(sp2)H bonds to aldehydes and nitriles is disclosed by virtue of a dual activation strategy. The reactions feature mild reaction conditions, excellent regio‐ and stereoselectivity, and a wide substrate scope, which includes both aromatic and olefinic CH bonds, as well as a large variety of aldehydes and nitriles. Moreover, mechanistic studies
unprecedented dual photoredox/palladium-catalyzed iminyl-radical-mediated C–C bond cleavage and directed ortho C–H acylation of 2-arylpyridines by using oxime esters is described. Oxime esters can serve as efficient acyl sources through formation of the corresponding acylradicals by photoredox-catalyzed iminyl-radical-mediated C–C bond cleavage. This redox-neutral protocol features excellent regioselectivity
Rh(III)‐Catalyzed Regioselective Acetylation of sp
<sup>2</sup>
C−H Bond Starting from Paraformaldehyde
作者:Ting Wan、Sidong Du、Chao Pi、Yong Wang、Rongbin Li、Yangjie Wu、Xiuling Cui
DOI:10.1002/cctc.201801512
日期:2019.8.21
Rh(III)‐catalyzedacetylation of sp2 C−H bonds has been realized using paraformaldehyde as an acetylating reagent. This procedure features simultaneous formation of two C−C bonds, external oxidants free, and water as the sole byproducts, thus offering an environmentally benign acetylation of arenes. A range of functional groups tolerance were observed.
Acylperoxycoumarins as<i>ortho</i>-CH Acylating Agent<i>via</i>a Palladium(II)-Catalyzed Redox-Neutral Process
作者:Prakash Ranjan Mohanta、Arghya Banerjee、Sourav Kumar Santra、Ahalya Behera、Bhisma K. Patel
DOI:10.1002/adsc.201600258
日期:2016.6.30
palladium(II)‐catalyzed biomimetic aliphatic acyl (‐COR) group transfer was observed from acyl‐α‐peroxycoumarins to the orthoCH sites of directingarenes. Here, the CH activation is associated with a concomitant acyl group transfer via a Pd(II)‐catalyzed, redox‐neutral process. While methods for ortho aroylation (‐COAr) are well documented ortho acylation (‐COR) processes are scarce, hence the present