Construction of Quaternary Stereocenters by Nickel‐Catalyzed Heck Cyclization Reactions
作者:Jean‐Nicolas Desrosiers、Liana Hie、Soumik Biswas、Olga V. Zatolochnaya、Sonia Rodriguez、Heewon Lee、Nelu Grinberg、Nizar Haddad、Nathan K. Yee、Neil K. Garg、Chris H. Senanayake
DOI:10.1002/anie.201606955
日期:2016.9.19
A nickel‐catalyzedHeckcyclization for the construction of quaternarystereocenters is reported. This transformation is demonstrated in the synthesis of 3,3‐disubstituted oxindoles, which are prevalent motifs seen in numerous biologically active molecules. The method shows broad scope, proceeds in synthetically useful yields, and provides a rare means to construct stereochemically complex frameworks
Oxindole Synthesis by Direct Coupling of C sp 2H and C sp 3H Centers
作者:Yi-Xia Jia、E. Peter Kündig
DOI:10.1002/anie.200805652
日期:——
An sp2/sp3 get‐together: A novel and efficient method can be used to synthesize 3,3‐disubstitued oxindoles by the direct intramolecular oxidative coupling of an aryl CH and a CH center (see scheme; DMF=N,N‐dimethylformamide).
alkylation of 3-hydroxy-oxindole derivatives is achieved. The reaction starts from addition of 4-dimethylaminopyridine (DMAP)-boryl radical to the amide carbonyl oxygen atom, which induces a spin-center shift process to promote the C–O bond cleavage. The elimination of a hydroxide anion from a free hydroxy group is also accomplished. Capture of the generated carbon radical with alkenes furnishes a variety
Trifluoroacetic Acid-Promoted Synthesis of 3-Hydroxy, 3-Amino and Spirooxindoles from α-Keto-<i>N</i>-Anilides
作者:Ioulia Gorokhovik、Luc Neuville、Jieping Zhu
DOI:10.1021/ol202263a
日期:2011.10.21
Ketoanilides containing alkyl side chains were readily cyclized to 3-hydroxy-2-oxindoles or spirooxindoles by a single or double intramolecular Friedel-Crafts reaction in the presence of trifluoroacetic acid (TFA) at room temperature or at 45 degrees C. alpha-Iminocarboxamides, generated in situ from ketoamides, cyclized similarly to 3-aminooxindoles under identical conditions,