Ka. Tehrani et al., Boron(III) bromide-induced ring contraction of 3-oxygenated piperidines to2-(bromomethyl)pyrrolidines, TETRAHEDR L, 41(14), 2000, pp. 2507-2510
3-Methoxypiperidines were converted into 2-(bromomethyl)pyrrolidines by rea
ction with boron(III) bromide in dichloromethane. This reaction proceeds vi
a an intermediate bicyclic aziridinium ion and features a rare conversion o
f piperidines into pyrrolidines. (C) 2000 Elsevier Science Ltd. All rights
reserved.