Ruthenium(II)-catalyzed Arylation of <i>ortho</i>-C–H Bonds in 2-Aroyl-imidazoles with Aryl Halides
作者:Chen-an Wang、Naoto Chatani
DOI:10.1246/cl.200886
日期:2021.4.5
The ruthenium(II)-catalyzed ortho-C−H arylation of 2-aroyl-imidazoles with aryl bromides and chloride is reported. An imidazole ring functions both as a masked ester and a directing group for C−H activation. A variety of functional groups are tolerated under the reaction conditions. The arylated final products could be easily converted into the corresponding esters and amide.
intermolecular 1,2-diacylation of alkenes is disclosed via cooperative N-heterocyclic carbene and photoredox catalysis under the mediation of PPh3 and Cs2CO3. This protocol provides a practical approach for construction of 1,4-dicarbonyl compounds toward novel diketone and pharmaceutical derivatives. Furthermore, the regioselective dicarbonyl compounds can be synthesized by adding acyl azolium salt. Mechanistic
在PPh 3和Cs 2 CO 3的介导下,通过协同的N-杂环卡宾和光氧化还原催化烯烃的分子间1,2-二酰化被公开。该协议为向新型二酮和药物衍生物构建 1,4-二羰基化合物提供了一种实用的方法。此外,区域选择性二羰基化合物可以通过添加酰基唑鎓盐来合成。机理研究表明,该过程是酮基自由基与苄基 C-自由基的关键自由基/自由基交叉偶联。
Ketone Synthesis via Irradiation-Induced Generation of a Persistent Ketyl Radical from Acyl Azolium Salts
A novel three-component α-acylated difunctionalization of alkenes strategy has been developed on the basis of a direct hydrogen atom transfer (HAT) process of photoinduced acyl azolium salts. With simple irradiation without the catalyst, a variety of olefins can be directly converted into ketone derivatives, including 1,4-dione, β-silyl ketone, 1,5-dione, etc. Mechanistic investigations indicated that
Carboxylate-Assisted Iridium (III)-Catalyzed C(sp<sup>2</sup>)–H Amidation of 2-Aroylimidazoles With Dioxazolones
作者:Sanjit K. Mahato、Naoto Chatani
DOI:10.1021/acs.joc.2c00949
日期:2022.6.17
Ir(III)-Catalyzed C(sp<sup>2</sup>)–H Amidation of 2-Aroylimidazoles with 2,2,2-Trichloroethoxycarbonyl Azide (TrocN<sub>3</sub>)
作者:Sanjit K. Mahato、Tianhao Zhang、Naoto Chatani
DOI:10.1021/acs.joc.2c02056
日期:2022.12.16
2-trichloroethyl azide (TrocN3) as an amidating reagent is reported. The reaction proceeds smoothly, even at room temperature, and various important functional groups are tolerated. The results of deuterium-labeling experiments indicate that C–H bond cleavage is irreversible and does not appear to be the rate-determining step. The presence of an electron-donating group on the phenyl ring in the 2-aroylimidazole