[2 + 2 + 1] Heteroannulation of Alkenes with Enynyl Benziodoxolones and Silver Nitrite Involving C≡C bond Oxidative Cleavage: Entry to 3-Aryl-Δ<sup>2</sup>-isoxazolines
作者:Cheng-Yong Wang、Fan Teng、Yang Li、Jin-Heng Li
DOI:10.1021/acs.orglett.0c01285
日期:2020.6.5
A copper-catalyzed [2 + 2 + 1] heteroannulation of alkenes with enynyl benziodoxolones and AgNO2 involving oxidative cleavage of the C≡C bond promoted by cooperative Zn(OTf)2, KOAc, and 4 Å MS for producing 3-aryl Δ2-isoxazolines is reported. Mechanistic studies indicate that AgNO2 serves as the N/O two-atom unit source, enabling the formation of three bonds through NO2 addition across the C≡C bond
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
Selective P−C(sp<sup>3</sup>
) Bond Cleavage and Radical Alkynylation of α-Phosphorus Alcohols by Photoredox Catalysis
作者:Kunfang Jia、Junzhao Li、Yiyun Chen
DOI:10.1002/chem.201800202
日期:2018.3.2
cleavage and radical alkynylation of α‐phosphorus alcohols to construct phosphonoalkynes is reported. The phosphorus radical is generated upon P−C bond cleavage reaction via the alkoxyl radical through photoredox catalysis with cyclic iodine(III) reagents. Various arylphosphinoyl‐, alkylphosphinoyl‐, phosphonate‐, and phosphonic amide alcohols serve as radical phosphorus precursors to construct phosphonoalkynes