<i>tert</i>-Butyl Nitrite-Mediated Synthesis of <i>N</i>-Nitrosoamides, Carboxylic Acids, Benzocoumarins, and Isocoumarins from Amides
作者:Subhash L. Yedage、Bhalchandra M. Bhanage
DOI:10.1021/acs.joc.7b00570
日期:2017.6.2
(TBN) as a multitask reagent for (1) the controlled synthesis of N-nitrosoamide from N-alkyl amides, (2) hydrolysis of N-methoxyamides to carboxylic acids, (3) metal- and oxidant-free benzocoumarin synthesisfrom ortho-aryl-N-methoxyamides via N–H, C–N, and C–H bond activation, and (4) isocoumarin synthesisusingRu(II)/PEG as a recyclable catalytic system via ortho-C–H activation and TBN as an oxygen source
作者:Qi-Liang Yang、Yi-Kang Xing、Xiang-Yang Wang、Hong-Xing Ma、Xin-Jun Weng、Xiang Yang、Hai-Ming Guo、Tian-Sheng Mei
DOI:10.1021/jacs.9b11915
日期:2019.12.4
Synergistic use of electrochemistry and organometallic catalysis has emerged as a powerful tool for site-selective C-H functionalization, yet this type of transformation has thus far mainly been limited to arene C-H functionaliza-tion. Herein, we report the development of electrochemi-cal vinylic C-H functionalization of acrylic acids with al-kynes. In this reaction an iridium catalyst enables C-H/O-H
A highly efficient rhodium(III)‐catalyzed directoxidative annulation of acrylicacid with alkynes to form α‐pyrones was developed. Various substituted acrylicacids were compatible in this transformation, affording the corresponding products in moderate to excellent yields under mild conditions.
The oxyindation of carbonyl-ene-yne compounds with indium trihalides proceeded efficiently to give di-, tri-, and tetrasubstituted 2-pyrones bearing a carbon-indium bond. The metalated 2-pyrone and a zwitterion intermediate were identified by X-ray crystallographic analysis. The application of organoindium compounds to oxidation or cross-coupling provided easy access to various multifunctionalized
Ruthenium(II)-Catalyzed Alkene C–H Bond Functionalization on Cinnamic Acids: A Facile Synthesis of Versatile α-Pyrones
作者:Rashmi Prakash、Kommuri Shekarrao、Sanjib Gogoi
DOI:10.1021/acs.orglett.5b02631
日期:2015.11.6
An inexpensive ruthenium(1) complex enabled oxidative annulation of alkynes by using cinnamic acid derivatives to provide diversely decorated multisubstituted alpha-pyrones.