A Practical Synthesis of Pyridylboranes via Magnesium-Halogen Exchange

Weiling Cai; David H. Brown Ripin

doi:10.1055/s-2002-19775

LETTER

A Practical Synthesis of Pyridylboranes via Magnesium-Halogen Exchange

Weiling Cai, David H. Brown Ripin*
Process Research and Development, Central Research Division, Pfizer Inc., Eastern Point Road, Groton, Connecticut 06340, USA
Fax: +1(860)4413630; e-Mail: David_B_Ripin@groton.pfizer.com;

Abstract

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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.

Key words

magnesium halogen exchange - pyridylborane - Grignard reagent - metalation

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References

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