Visible-light-mediated selective thiocyanation/ipso-cyclization/oxidation cascade for the synthesis of thiocyanato-containing azaspirotrienediones
作者:Yuan Chen、Yu-Jue Chen、Zhi Guan、Yan-Hong He
DOI:10.1016/j.tet.2019.130763
日期:2019.12
visible-light-mediated metal-free thiocyanate radicaladdition/ipso-cyclization/oxidation cascade reaction for the synthesis of thiocyanato-containing azaspirotrienediones from N-phenylpropynamides is described. Cheap and readily available ammonium thiocyanate was used as a precursor to the thiocyanate freeradical, which undergoes a radicaladditionreaction with the alkyne, followed by selective ipso-cyclization
Silver-catalyzed direct spirocyclization of alkynes with thiophenols: a simple and facile approach to 3-thioazaspiro[4,5]trienones
作者:Huanhuan Cui、Wei Wei、Daoshan Yang、Jimei Zhang、Zhihong Xu、Jiangwei Wen、Hua Wang
DOI:10.1039/c5ra16548b
日期:——
A new and convenient silver-catalyzed direct oxidative spirocyclization of alkynes with thiophenols is described. This methodology provides a simple and practical approach to various 3-thioazaspiro[4,5]trienones in moderate to good yields with high atom efficiency and excellent functional group tolerance.
Dual Hypervalent Iodine(III) Reagents and Photoredox Catalysis Enable Decarboxylative Ynonylation under Mild Conditions
作者:Hanchu Huang、Guojin Zhang、Yiyun Chen
DOI:10.1002/anie.201502369
日期:2015.6.26
combination of hypervalentiodine(III) reagents (HIR) and photoredoxcatalysis with visible light has enabled chemoselective decarboxylativeynonylation to construct ynones, ynamides, and ynoates. This ynonylation occurs effectively undermild reaction conditions at room temperature and on substrates with various sensitive and reactive functional groups. The reaction represents the first HIR/photoredox dual
Selective Carbonyl−C(sp<sup>3</sup>) Bond Cleavage To Construct Ynamides, Ynoates, and Ynones by Photoredox Catalysis
作者:Kunfang Jia、Yue Pan、Yiyun Chen
DOI:10.1002/anie.201611897
日期:2017.2.20
Carbon–carbonbondcleavage/functionalization is synthetically valuable, and selective carbonyl−C(sp3) bondcleavage/alkynylation presents a new perspective in constructing ynamides, ynoates, and ynones. Reported here is the first alkoxyl‐radical‐enabled carbonyl−C(sp3) bondcleavage/alkynylation reaction by photoredox catalysis. The use of novel cyclic iodine(III) reagents are essential for β‐carbonyl
A direct electrochemical oxidative cyclization of alkynoates and alkynamides with diselenides or disulfides for the synthesis of coumarins and quinolinones bearing a chalcogen functional group has been developed. This green and efficient approach was realized through a constant current electrolysis in an undivided cell under metal-free and oxidant-free conditions. Moreover, a series of selenium/sulfur-substituted