3-(N,N-Dimethylamino)propan-1-ol readily reacts at room temperature with aryl alpha-bromoacetophenones to form N-(3-hydroxypropyl)-N,N-dimethyl-N-[2-oxo-2-arylethyl]ammonium bromides in yields up to 89%. Contrary to a previous report (J. Med. Chem. 1966, 9, 211-213), the seven-membered ring hemiketal is not formed. An X-ray structure of the 4-phenylphenyl compound shows the open form.