Base-Promoted Selective Synthesis of 2-Pyranones and Tetrahydronaphthalenes via Domino Reactions.

ACS Omega

Department of Organic Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai 625021, Tamilnadu, India.

Published: August 2017

A highly efficient domino protocol has been developed for the synthesis of 6-aryl-4-(methylthio/amine-1-yl)-2-oxo-2-pyran-3-carbonitriles and 4-aryl-2-(amine-1-yl)-5,6,7,8-tetrahydronaphthalene-1-carbonitriles from simple and readily available α-aroylketene dithioacetals, malononitrile, secondary amines, and cyclohexanone. This elegant domino process involved consecutive addition-elimination, intramolecular cyclization, and ring opening and closing sequences. Notably, in situ generated 2-imino-4-(methylthio/amine-1-yl)-6-aryl-2-pyran-3-carbonitrile plays multiple roles in the construction of various novel polyaromatic hydrocarbons.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6641896PMC
http://dx.doi.org/10.1021/acsomega.7b00627DOI Listing

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