Filipponi, Paolo, Martin, Benjamin, Knochel, Paul, Heinz, Benjamin and Djukanovic, Dimitrije (2021) Regioselective Difunctionalization of Pyridines via 3,4-Pyridynes. Chemical Science, 12. pp. 6143-6147. ISSN https://doi.org/10.1039/D1SC01208H

Abstract

A new regioselective 3,4-difunctionalization of 3 chloropyridines via 3,4-pyridyne intermediates is reported. Regioselective lithiation of 3-chloro-2-ethoxypyridine and a related 2-thio-derivative followed by treatment with aryl- and alkylmagnesium halides as well as magnesium thiolates at 78 °C produced 3,4-pyridynes during heating to 75 °C. Regioselective addition of the Grignard moiety in position 4 followed by an electrophilic quench in position 3 led to various 2,3,4-trisubstituted pyridines. This method was adapted into a continuous flow set-up. As an application, we have prepared a key intermediate for the antidepressant (±) paroxetine.

Item Type:	Article
Keywords:	pyridines, pyridynes, organometallic chemistry, flow chemistry
Date Deposited:	25 May 2021 00:45
Last Modified:	25 May 2021 00:45
URI:	https://oak.novartis.com/id/eprint/44205