Palladium-catalyzed approach for the general synthesis of (E)-2-arylmethylidene-N-tosylindolines and (E)-2-arylmethylidene-N-tosyl/nosyltetrahydroquinolines: access to 2-substituted indoles and quinolines.

Abstract

A facile and efficient method for the synthesis of (E)-2-arylmethylidene-N-tosylindolines and (E)-2-arylmethylidene-N-tosyl/nosyltetrahydroquinoline variants has been developed through palladium-catalyzed cyclocondensation of aryl iodides with readily available 1-(2-tosylaminophenyl)prop-2-yn-1-ols and their higher homologues, respectively. The proposed reaction mechanism invokes the operation of trans-aminopalladation during cyclization (5/6-exo-dig), which ensures exclusive (E)-stereochemistry in the products. The method is fast, operationally simple, totally regio- and stereoselective, and versatile enough to access a variety of 2-substituted indoles and quinolines. The reactions proceeded efficiently with a wide variety of substrates and afforded the corresponding products in moderate to excellent yields.

DOI: 10.1021/jo300458v

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Cite this paper

@article{Chowdhury2012PalladiumcatalyzedAF, title={Palladium-catalyzed approach for the general synthesis of (E)-2-arylmethylidene-N-tosylindolines and (E)-2-arylmethylidene-N-tosyl/nosyltetrahydroquinolines: access to 2-substituted indoles and quinolines.}, author={Chinmay Chowdhury and Bimolendu Das and Sanjukta Mukherjee and B. Naresh Achari}, journal={The Journal of organic chemistry}, year={2012}, volume={77 11}, pages={5108-19} }