Rhodium(III)-Catalyzed Redox-Neutral CH Annulation of Arylnitrones and Alkynes for the Synthesis of Indole Derivatives
作者:Zhi Zhou、Guixia Liu、Yan Chen、Xiyan Lu
DOI:10.1002/adsc.201500580
日期:2015.9.14
By using a nitrone as the oxidizingdirectinggroup, a mild, practical and efficient rhodium(III)‐catalyzed CH functionalization for the synthesis of indole derivatives has been developed. This reaction obviates the need for an external oxidant and shows good functional group tolerance. The employment of a sterically hindered Mes group on the carbon center of the nitrone is crucial to produce indoles
Dissecting the Electronic Contribution to the Regioselectivity of the Larock Heteroannulation Reaction in the Oxidative Addition and Carbopalladation Steps
作者:Kanyapat Yiamsawat、Kevin P. Gable、Pitak Chuawong
DOI:10.1021/acs.joc.1c02560
日期:2022.1.21
the regiochemical outcome of the reaction. Density functional theory calculations of the oxidative addition and carbopalladation steps revealed the electronic influences of the substituted 2-iodoaniline derivatives toward the overall rate of the reaction. In contrast, the electronic properties of the asymmetric diarylacetylene remained the critical product-determining factor of regioselectivity.
Selective Synthesis of <i>N</i>-Unsubstituted and <i>N</i>-Arylindoles by the Reaction of Arynes with Azirines
作者:Manikandan Thangaraj、Sachin Suresh Bhojgude、Shailja Jain、Rajesh G. Gonnade、Akkattu T. Biju
DOI:10.1021/acs.joc.6b01472
日期:2016.9.16
transition-metal-free and temperature-dependent highly selective reaction of arynes with 2H-azirines allowing the synthesis of either N-unsubstituted or N-arylindoles has been developed. At 60 °C, arynes generated from 2-(trimethylsilyl)aryl triflates smoothly insert into 2H-azirines to form 2,3-diarylindoles with high selectivity. Interestingly, when the reaction was performed at −10 °C, the selectivity was switched
A series of 2,3-diarylindoles were synthesized from 2-iodoaniline and unsymmetrical diarylacetylenes using the Larock heteroannulation. Diarylacetylenes bearing electron-withdrawing substituents lead to 2,3-diarylindoles with substituted phenyl moieties at the 2-position as major products, while those with electron-donating groups preferably yield indole products with substituted phenyl moieties at the 3-position. The regioisomeric product ratios exhibit a clear correlation with Hammett sigma(p) values. DFT calculations reveal the origin of this effect, displaying smaller activation energy barriers for those pathways leading to the major regioisomer.
A synthetic 2,3-diarylindole induces cell death via apoptosis and autophagy in A549 lung cancer cells
A series of 2,3-diarylindoles were synthesized via the Larock heteroannulation, and evaluated for their anticancer activity against A549 lung cancer cells. The most potent compound, PCNT13 with IC50 = 5.17 mu M, caused the induction of two modes of programmed cell death, apoptosis and autophagy. (C) 2016 Elsevier Ltd. All rights reserved.