A Practical Synthesis of Pyridylboranes via Magnesium-Halogen Exchange

Abstract

Dialkylpyridylboranes can be prepared by the reaction of the corresponding pyridylmagnesium chloride with diethylmethoxyborane at 0-25 °C. The pyridylmagnesium chlorides are generated from the corresponding bromopyridines via magnesium-halogen exchange reaction.

magnesium halogen exchange - pyridylborane - Grignard reagent - metalation

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<A NAME="RS08301ST-8">8</A>

All products have been fully characterized by spectroscopic methods after isolation by crystallization.