E. Leonel et al., A simple and efficient procedure for the preparation of benzal chlorides and benzal bromides, SYN COMMUN, 29(22), 1999, pp. 4015-4024
benzal chlorides and benzal bromides were conveniently synthesized by react
ion of aryl aldehydes with a Vilsmeier type reagent formed in situ by reduc
tion of CCl4 or CBr4 in dimethylformamide (DMF) as solvent.