Iodine/Visible Light Photocatalysis for Activation of Alkynes for Electrophilic Cyclization Reactions
作者:Yuliang Liu、Bin Wang、Xiaofeng Qiao、Chen-Ho Tung、Yifeng Wang
DOI:10.1021/acscatal.7b00799
日期:2017.6.2
Photocatalytic organic synthesis needs photocatalysts to initiate the reactions and to control the reaction paths. Available photocatalytic systems rely on electron transfer or energy transfer between the photoexcited catalysts and the substrates. We explore a concept based on the photopromoted catalyst coupling to the substrate and the phototriggered catalyst regeneration by elimination from the catalytic
Preparation of oxazolines and oxazoles<i>via</i>a PhI(OAc)<sub>2</sub>-promoted cyclization of<i>N</i>-propargylamides
作者:Wei Yi、Qing-Yun Liu、Xing-Xiao Fang、Sheng-Chun Lou、Gong-Qing Liu
DOI:10.1039/c8ob01474d
日期:——
A metal-free cyclization of N-propargylamides for the synthesis of various oxazolines and oxazoles via a 5-exo-dig process is presented. Using (diacetoxyiodo)benzene (PIDA) as a reaction promoter and lithium iodide (LiI) as an iodine source, intramolecular iodooxygenation of N-propargylamides proceeded readily, leading to the corresponding (E)-5-iodomethylene-2-oxazolines in good to excellent isolated
Abstract Straightforward and direct synthesis of 2-substituted-5-oxazolecarbaldehydes was achieved by treating propargylamides with mercury(II) perchlorate as catalyst and ammonium cerium(IV) nitrate as oxidant agent through intramolecular cyclization. These structurally interesting outcomes benefit to synthesize 2,5-disubstituted-1,3-oxazoles with armyworm growth regulating activities.