Hammick reaction

The Hammick reaction is a chemical reaction described as a thermal decarboxylation of α-picolinic (or related) acids in the presence of carbonyl compounds to form 2-pyridyl-carbinols.^[1][2]

Additional recommended knowledge

What is the Correct Way to Check Repeatability in Balances?

Recognize and detect the effects of electrostatic charges on your balance

How to ensure accurate weighing results every day?

Using p-cymene as solvent has been shown to increase yields.^[3]

Reaction mechanism

Upon heating α-picolinic acid will spontaneously decarboxylate forming a zwitterion (2). In the presence of a strong electrophile, such as an aldehyde, the zwitterion will react with the carbonyl faster than protonating. Upon proton transfer the desired carbinol (4) is formed.

References

1. ^  (a) Dyson, P.; Hammick, D. L. J. Chem. Soc. 1937, 1724. (b) Hammick, D. L.; Dyson, P. J. Chem. Soc. 1939, 809.
2. ^  Brown, E. V.; Shambhu, M. B. J. Org. Chem. 1971, 36, 2002. (doi:10.1021/jo00813a034)
3. ^  Sperber, N.; Papa, D.; Schwenk, E.; Sherlock, M. J. Am. Chem. Soc. 1949, 71, 887.