Visible-Light-Photocatalyzed Synthesis of Phenanthridinones and Quinolinones via Direct Oxidative C–H Amidation
摘要:
A straightforward synthetic strategy to construct biologically relevant phenanthridinones and quinolinones was developed via visible-light-promoted direct oxidative C-H amidation. In this photocatalytic system, amidyl radicals can be generated by homolysis of the N-H bond of simple amide precursors via single-electron transfer under blue LED illumination, which leads to oxidative intramolecular C-H amidation. Moreover, an efficient synthetic strategy using a photocascade enabled facile assembly of quinolinone structures through a catalytic sequence involving triplet energy (E-T) transfer based E/Z olefin isomerization and subsequent photocatalytic generation of amidyl radical intermediates.
DDQ-promoted direct transformation of benzyl hydrocarbons to amides via tandem reaction of the CDC reaction and Beckmann rearrangement
作者:Jun Qiu、Ronghua Zhang
DOI:10.1039/c3ob41218k
日期:——
An atom-efficient and transition metal-free approach to amides from the corresponding benzyl hydrocarbons through C–H and C–C bond cleavage has been developed. Mechanistic studies have shown that a DDQ-promoted cross-dehydrogenative coupling (CDC) reaction with subsequent oxidation and rearrangement are involved in this transformation.
Direct Amidation of Carboxylic Acids with Nitroarenes
作者:Shao-Peng Wang、Chi Wai Cheung、Jun-An Ma
DOI:10.1021/acs.joc.9b02068
日期:2019.11.1
N-Aryl amides are an important class of compounds in pharmaceutical and agrochemical chemistry. Rapid and low-cost synthesis of N-aryl amides remains in high demand. Herein, we disclose an operationally simple process to access N-aryl amides directly from readily available nitroarenes and carboxylicacids as coupling substrates. This method involves the in situ activation of carboxylicacids to acyloxyphosphonium
Copper-Catalyzed Direct Transformation of Secondary Allylic and Benzylic Alcohols into Azides and Amides: An Efficient Utility of Azide as a Nitrogen Source
作者:Balaji V. Rokade、Karthik Gadde、Kandikere Ramaiah Prabhu
DOI:10.1002/ejoc.201500010
日期:2015.4
synthesis of amides has been explored by using secondary alcohols, Cu(ClO4)2·6H2O as a catalyst, and trimethylsilyl azide (TMSN3) as a nitrogen source in the presence of 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) at ambient temperature. This method has been successfully adapted to the preparation of azides directly from their corresponding alcohols and offers excellent chemoselectivity in the formation
Manganese(I) Catalyzed α-Alkenylation of Amides Using Alcohols with Liberation of Hydrogen and Water
作者:Biplab Keshari Pandia、Chidambaram Gunanathan
DOI:10.1021/acs.joc.1c00685
日期:2021.8.6
Herein, unprecedented manganese-catalyzed direct α-alkenylation of amides using alcohols is reported. Aryl amides are reacted with diverse primary alcohols, which provided the α,β-unsaturated amides in moderate to good yields with excellent selectivity. Mechanistic studies indicate that Mn(I) catalyst oxidizes the alcohols to their corresponding aldehydes and also plays an important role in efficient
Synthesis of Linear α,β-Unsaturated Amides from Isocyanates and Alkenylaluminum Reagents
作者:Xiao-Feng Wu、Bo Chen
DOI:10.1055/s-0037-1610753
日期:2020.5
A new approach has been developed for the synthesis of linear α,β-unsaturated amides by the direct coupling of isocyanates with alkenylaluminum reagents. At room temperature, the desired α,β-unsaturated amides were isolated in good to excellent yields with good functional-group tolerance in the absence of any catalyst or additive.