Fe/S-Catalyzed synthesis of 2-benzoylbenzoxazoles and 2-quinolylbenzoxazoles <i>via</i> redox condensation of <i>o</i>-nitrophenols with acetophenones and methylquinolines
作者:Le Anh Nguyen、Thi Thu Tram Nguyen、Quoc Anh Ngo、Thanh Binh Nguyen
DOI:10.1039/d1ob00976a
日期:——
An Fe/S catalyst generated in situ from FeCl2·4H2O and elemental sulfur S8 in the presence of a tertiary amine as a base was found to catalyze efficiently a 6e− redox condensation of o-nitrophenols with acetophenones and methylquinolines. The condensed products 2-benzoylbenzoxazoles and 2-quinolylbenzoxazoles were obtained in reasonable yields with water as the only byproduct at a temperature as low
发现在叔胺作为碱存在下由 FeCl 2 ·4H 2 O 和元素硫 S 8原位生成的 Fe/S 催化剂可有效催化邻硝基苯酚与苯乙酮和甲基喹啉的 6e -氧化还原缩合反应。缩合产物 2-苯甲酰基苯并恶唑和 2-喹啉基苯并恶唑在低至 80 °C 的温度下以合理的收率获得,水作为唯一的副产物。
Break‐and‐Build Strategy for the Synthesis of 2‐Benzoylbenzoxazoles from
<i>o</i>
‐Aminophenols and Acetophenones
作者:Le Anh Nguyen、Quoc Anh Ngo、Pascal Retailleau、Thanh Binh Nguyen
DOI:10.1002/adsc.202100150
日期:2021.4.13
required substrates bearing activating groups. Herein, we report an efficient method for the synthesis of such compounds by direct reactions of o‐aminophenols with acetophenones promoted by sulfur in DMSO. The reaction was found to proceed via a Willgerodt rearrangement‐type benzoxazolation of acetophenones followed by a benzylic oxidation to reinstall the carbonyl function. This method has a broad
Nickel-Catalyzed Decarboxylative Acylation of Heteroarenes by sp<sup>2</sup>CH Functionalization
作者:Ke Yang、Cheng Zhang、Peng Wang、Yan Zhang、Haibo Ge
DOI:10.1002/chem.201402516
日期:2014.6.10
azole derivatives with α‐oxoglyoxylic acids has been developed. This work represents the first example of decarboxylative cross‐coupling reactions, in a CH bond functionalization manner, through nickel catalysis, and tolerates various functional groups. Additionally, this approach provides an efficient access to azole ketones, an important structural motif in many medicinal compounds with a broad
Cobalt-Catalyzed Decarboxylative 2-Benzoylation of Oxazoles and Thiazoles with α-Oxocarboxylic Acids
作者:Ke Yang、Xinyong Chen、Yuqi Wang、Wanqing Li、Adnan A. Kadi、Hoong-Kun Fun、Hao Sun、Yan Zhang、Guigen Li、Hongjian Lu
DOI:10.1021/acs.joc.5b01450
日期:2015.11.6
Cobalt-catalyzed decarboxylative cross-coupling of oxazoles and thiazoles with alpha-oxocarboxylic acids was developed through an sp(2) C-H bond functionalization process. This work represents the first example of cobalt-catalyzed decarboxylative C-H bond functionalization and provides an efficient means of building some important bioactive heteroaryl ketone derivatives.