A practical and efficient radical coupling of easily available arylthiodifluoroacetic acids and ethynylbenziodoxolone (EBX) reagents has been reported. Under transition metal-free conditions, aryl-substituted EBXs were converted to the corresponding ArSCF2-substituted alkynes in moderate to good yields, whereas TIPS-EBX underwent silver-catalyzed decarboxylative conditions to deliver the desired coupling
A general and efficient method for the direct alkynylation of unactivatedC(sp3)-H bondsunder metal-free condition is described. The reaction smoothly performs undermildconditions and shows excellent functional-group tolerance....
A transition-metal-free synthetic method of various ynones via decarboxylative alkynylation of α-keto acids is described. The reaction is carried out undermildconditions and exhibits remarkable tolerance of functional groups. The mechanism of a radical process is proposed in the reaction.
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