Under new conditions described herein, halogenolactamization of 2-(3-butenyl)-1,3-oxazolines (1) proves to be a successful approach for producing 1,5-bis(halogenoalkyl)-γ-lactams (3). A variety of halogens can be introduced by using reagents such as I2, I2/CuCl2, I2/CuBr2, and Br2 under dry conditions.