A Tandem Strategy for the Synthesis of 1<i>H</i>-Benzo[<i>g</i>]indazoles and Naphtho[2,1-<i>d</i>]isoxazoles from<i>o</i>-Alkynylarene Chalcones
作者:Sikkandarkani Akbar、Kannupal Srinivasan
DOI:10.1002/ejoc.201201576
日期:2013.3
o-Alkynylarene chalcones when treated with hydrazines and hydroxylamine in the presence of iodine gave 1H-benzo[g]indazoles and naphtho[2,1-d]isoxazoles, respectively. The transformations involve tandem oxidative cyclocondensation/electrophilic hydroarylation. The methodology was applied to quinoline-based chalcones, which also afforded the corresponding quinoline-fused benzindazole and benzisoxazole
A [3 + 2] cycloaddition of indanone-derived nitrones and alkynes under mild conditions is developed, allowing facile synthesis of spirocyclicindenyl isoxazolines with structural diversity. The sequential protocol of generated in situ ketonitrone from unsaturated ketones and N-alkylhydroxylamines is also achieved successfully, affording the desired products in considerable yield with moderate to good
Iron-Catalyzed Tandem Conia–Ene/Friedel–Crafts Reactions of <i>o</i>-Alkynyldihydrochalcones: Access to Benzo[<i>b</i>]fluorenes
作者:Sikkandarkani Akbar、Kannupal Srinivasan
DOI:10.1021/acs.joc.5b02391
日期:2016.2.5
o-Alkynyldihydrochalcones when treated with a catalytic amount of anhydrous FeCl3 in refluxing 1,2-dichloroethane underwent tandem Conia–ene and Friedel–Craftsreactions to yield benzo[b]fluorenederivatives in good yields.
在回流的1,2-二氯乙烷中用催化量的无水FeCl 3处理邻-炔基二氢查耳酮时,串联进行Conia-ene和Friedel-Crafts反应,以高收率得到苯并[ b ]芴衍生物。
Iodine-Catalyzed Synthesis of Highly Functionalized 1<i>H</i>-Indene Derivatives from Michael Adducts of<i>o</i>-Alkynylarene Chalcones with Diethyl Malonate
作者:Sikkandarkani Akbar、Kannupal Srinivasan
DOI:10.1002/ejoc.201501141
日期:2015.12
Upon treatment with a substoichiometric amount of iodine in ethanol under reflux conditions, the Michaeladducts of o-alkynylarene chalcones with diethylmalonate underwent 5-exo-dig Conia-ene cyclization followed by isomerization to yield highlyfunctionalized1H-indenederivatives in good yields.