Visible-Light-Promoted Dual C–C Bond Formations of Alkynoates via a Domino Radical Addition/Cyclization Reaction: A Synthesis of Coumarins
作者:Shangbiao Feng、Xingang Xie、Weiwei Zhang、Lin Liu、Zhuliang Zhong、Dengyu Xu、Xuegong She
DOI:10.1021/acs.orglett.6b01857
日期:2016.8.5
difunctionalization of alkynoates has been accomplished. This procedure provides a new strategy toward synthesis of the coumarin core structure by photoredox-mediated oxidation to generate the α-oxo radical, which supervenes a dominoradical addition/cyclization reaction in moderate to good yields with high regioselectivity at ambient temperature.
Visible-light initiated oxidative cyclization of phenyl propiolates with sulfinic acids to coumarin derivatives under metal-free conditions
作者:Wenchao Yang、Shuai Yang、Pinhua Li、Lei Wang
DOI:10.1039/c5cc00878f
日期:——
A visible-light initiated oxidative cyclization of phenyl propiolates with sulfinic acids has been developed at room temperature under metal-free conditions.
oxidative difunctionalization of aryl alkynoates at room temperature to access stereodefined fully substituted α,β-unsaturated acids bearing a chalcogen functionality in high yields (up to 95%). The protocol is operationally simple, metal-free, scalable, and suppresses the usual CO2 exclusion phenomenon. The utility of this method was showcased in the synthesis of vinyl halides, vinyl selenides, and
Catalyst-free synthesis of α-thioacrylic acids <i>via</i> cascade thiolation and 1,4-aryl migration of aryl alkynoates at room temperature
作者:Wei Wei、Leilei Wang、Huilan Yue、Yuan-Ye Jiang、Daoshan Yang
DOI:10.1039/c8ob01349g
日期:——
A simple and facile catalyst-free strategy has been developed for the synthesis of α-thioacrylic acids from readily-available aryl alkynoates and thiols at room temperature under air.
The visible-light-induced acylation/cyclization of alkynoates with acyl oximes for the construction of 3-acylcoumarins
作者:Quan Zhou、Fang-Ting Xiong、Pu Chen、Bi-Quan Xiong、Ke-Wen Tang、Yu Liu
DOI:10.1039/d1ob01568k
日期:——
by the visible-light-induced acylation/cyclization of alkynoates with various acyl oximecompounds in acetonitrile. The difunctionalization of carbon–carbon triple bonds precedes the generation of iminyl radicals, which is followed by the formation of acyl radicals. The acyl radicals then attack the carbon–carbon triple bonds, followed by 5-exo-trig cyclization and 1,2-ester migration. This strategy