A Direct CH/ArH Coupling Approach to Oxindoles, Thio‐oxindoles, 3,4‐Dihydro‐1
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‐quinolin‐2‐ones, and 1,2,3,4‐Tetrahydroquinolines
作者:Timothy E. Hurst、Ryan M. Gorman、Pauline Drouhin、Alexis Perry、Richard J. K. Taylor
DOI:10.1002/chem.201403917
日期:2014.10.20
A copper(II)‐catalysed approach to oxindoles, thio‐oxindoles, 3,4‐dihydro‐1H‐quinolin‐2‐ones, and 1,2,3,4‐tetrahydroquinolines via formal CH, ArHcoupling is described. In a new variant, copper(II) 2‐ethylhexanoate has been identified as an inexpensive and efficient catalyst for this transformation, which utilises atmospheric oxygen as the re‐oxidant.
Low-Temperature, Transition-Metal-Free Cross-Dehydrogenative Coupling Protocol for the Synthesis of 3,3-Disubstituted Oxindoles
作者:James R. Donald、Richard J. K. Taylor、Wade F. Petersen
DOI:10.1021/acs.joc.7b02085
日期:2017.10.20
strong, nonreversible base in these reactions has been found to effect a dramatic drop in reaction temperature (to room temperature) relative to the current state-of-the-art (>100 °C) procedure. When employing iodine as an “oxidant”, new evidence suggests that this transformation may occur via a transiently stable iodinated intermediate rather than by direct single-electron oxidation.
A novel method for the synthesis of 2‐oxindoles from 1,3‐dicarbonyl compounds based on ferrous salt and iodide catalyst was described. Through a new catalytic oxidation system, the intramolecular dehydrogenation coupling reaction was completed by using catalytic amount of iodine.
First C−H Activation Route to Oxindoles using Copper Catalysis
作者:Johannes E. M. N. Klein、Alexis Perry、David S. Pugh、Richard J. K. Taylor
DOI:10.1021/ol1012668
日期:2010.8.6
The preparation of 3,3-disubstituted oxindoles by a formal C-H, Ar-H coupling of anilides is described. Highly efficient conditions have been Identified using catalytic (5 mol %) Cu(OAc)(2)center dot H(2)O with atmospheric oxygen as the reoxidant; no additional base is required, and the reaction can be run in toluene or mesitylene. Optimization studies are reported together with a scope and limitation investigation based on variation of the anilide precursors. The application of this methodology to prepare a key Intermediate for the total synthesis of the anticancer, analgesic oxindole alkaloid Horsfiline is also described.