Versatile synthesis of 3,5-disubstituted 2-fluoropyridines and 2-pyridones.

Andrew Sutherland, Timothy Gallagher

Index: J. Org. Chem. 68(8) , 3352-5, (2003)

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Abstract

5-bromo-2-fluoro-3-pyridylboronic acid (3) was prepared in high yield by ortho-lithiation of 5-bromo-2-fluoropyridine (1), followed by reaction with trimethylborate. Suzuki reaction of 3 with a range of aryl iodides gave 3-monosubstituted 5-bromo-2-fluoropyridines 4 in excellent yields. A second Suzuki reaction utilizing the bromo constituent of 4 with aryl and heteroaryl boronic acids provided 3,5-disubstituted 2-fluoropyridines 5, which in turn could be converted to the corresponding 2-pyridones 6.