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.
Synthesis of N-alkyl isatins via oxidative cyclization of N-alkyl 2-bromo(chloro)acetanilides
作者:Qingwen Gui、Fenglin Dai、Jidan Liu、Peixing Chen、Zhiyong Yang、Xiang Chen、Ze Tan
DOI:10.1039/c4ob00118d
日期:——
A highly efficient method for the synthesis of N-alkyl isatins starting from N-alkyl 2-bromo or 2-chloro acetanilides is described. The starting materials are easy to prepare and the yields of isatins are generally high. Operationally the reaction is very simple to run. Even though best results were obtained with a catalytic amount of CuI, the reactions of N-alkyl 2-bromo acetanilides actually performed well even in the absence of any metal catalyst.
Electrochemical dehydrogenative cyclization of 1,3-dicarbonyl compounds
作者:Zheng-Jian Wu、Shi-Rui Li、Hao Long、Hai-Chao Xu
DOI:10.1039/c8cc02472c
日期:——
The intramolecular C(sp3)–H/C(sp2)–H cross-coupling of 1,3-dicarbonyl compounds has been achieved through Cp2Fe-catalyzed electrochemical oxidation. The key to the success of these dehydrogenative cyclization reactions is the selective activation of the acidic α-C–H bond of the 1,3-dicarbonyl moiety to generate a carbon-centered radical.
A copper(II)-mediated radical cross-dehydrogenative coupling/sulfinic acid elimination approach to 2-quinolones
作者:Ryan M. Gorman、Timothy E. Hurst、Wade F. Petersen、Richard J.K. Taylor
DOI:10.1016/j.tet.2019.130711
日期:2019.12
cyclisation procedure to prepare 4-carboxy-quinolin-2-ones via a one-pot Cu(II)-mediated radical cross-dehydrogenative coupling/sulfinicacid elimination of linear anilides is described. Extensions to more complex substrates are also reported as are applications in target synthesis allowing access to natural products isolated from Oryza sativa and HOFQ.