Visible-light-mediated radical cascade reaction: synthesis of 3-bromocoumarins from alkynoates
作者:Shangbiao Feng、Jinlai Li、Zaimin Liu、Haiyu Sun、Hongliang Shi、Xiaolei Wang、Xingang Xie、Xuegong She
DOI:10.1039/c7ob02199b
日期:——
The development of a visible-light mediated bromo radical addition/spirocyclization/ester migration cascade reaction to generate 3-bromocoumarins from alkynoates is reported.
报道了一种利用可见光介导的溴自由基加成/螺环化/酯迁移串联反应,从炔酸酯生成3-溴香豆素。
Anionic O → α- and β-Vinyl Carbamoyl Translocation of 2-(<i>O</i>-Carbamoyl) Stilbenes
作者:Mark A. Reed、Michelle T. Chang、Victor Snieckus
DOI:10.1021/ol049740t
日期:2004.7.1
[reaction: see text] New anionic oxygen to alpha- and beta-vinyl carbamoyl migration reactions, 17a and 26a-c --> 18 and 30a-c, proceed under LDA-mediated conditions leading stereoselectively to highly substituted stilbenes bearing electron-donating and -withdrawing substituents. Compounds 17a and 26a-c are prepared by combination of efficient, directedorthometalation, Sonogashira, and Suzuki-Miyaura
An expeditious and regioselective approach towards the construction of a spiro-chroman motif is described. Quinonemethides underwent a PTSA catalyzed annulation with 2-benzylidene dithiolanes to afford spiro-chroman dithiolanes in high yields. The synthetic versatility of the dithiolane motif was demonstrated by converting the adduct to coumarin, 3,4-dihydrocoumarin and chroman derivatives.
Arora, P. K.; Ray, Suprabhat, Journal fur praktische Chemie (Leipzig 1954), 1981, vol. 323, # 5, p. 850 - 852
作者:Arora, P. K.、Ray, Suprabhat
DOI:——
日期:——
General and Efficient Route for the Synthesis of 3,4-Disubstituted Coumarins via Pd-Catalyzed Site-Selective Cross-Coupling Reactions
作者:Liang Zhang、Tianhao Meng、Renhua Fan、Jie Wu
DOI:10.1021/jo071117+
日期:2007.9.1
Palladium-catalyzed site-selective cross-couplingreactions of 3-bromo-4-trifloxycoumarin or 3-bromo-4-tosyloxycoumarin provide an efficient and facile route for the synthesis of 3,4-disubstituted coumarins, which include 3,4-diarylcoumarins, 3-amino-4-arylcoumarins, and 3-aryl-4-aminocoumarins. The order of reactivity of the (pseudo)halide substituents in the coumarins was found to be 4-OTf > 3-Br