Concise synthesis of multisubstituted isoquinolines from pyridines by regioselective Diels-Alder reactions of 2-silyl-3,4-pyridynes.

Chemistry

Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan), Fax: (+81) 6-6879-8212, (+81) 6-6879-8210.

Published: December 2014

A four-step regioselective synthesis of multisubstituted isoquinoline derivatives from 3-bromopyridines was developed by the Diels-Alder (DA) reactions of 2-silyl-3,4-pyridynes with furans, followed by functional-group transformations. In particular, the silyl group at the C2-position of the 3,4-pyridynes played two important roles: firstly, it functioned as the directing group for the DA reaction, and secondly, it served to introduce diverse substituents at the C1-position of the isoquinolines by electrophilic ipso-substitution.

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http://dx.doi.org/10.1002/chem.201404633DOI Listing

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