Jc. Schmidhauser et Ff. Khouri, REARRANGEMENT OF 2-(HALOALKOXY)PYRIDINES TO N-HALOALKYL-2(1H)-PYRIDONES, Tetrahedron letters, 34(42), 1993, pp. 6685-6688
2-(Haloalkoxy)pyridines thermally rearrange to N-haloalkyl-2(1H)-pyrid
ones in high Yield. The reaction rate is accelerated by use of a more
polar solvent, by bromine rather than chlorine as the halogen substitu
ent and by a two-carbon alkoxy chain as opposed to a three or, especia
lly, four-carbon chain. The reaction kinetics can be interpreted in te
rms of an oxazolium ion intermediate.