Regioselective Difunctionalization of Pyridines via 3,4-Pyridynes
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 |
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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 |