Photoreactions of 1-(2-naphthoyl)aziridine (NAz) have been investigated in various solvents under the deaerated conditions at room temperature. The photo-irradiation of NAz in halogenated hydrocarbons afforded halogen substituted secondary amides such as N-(2-chloroethyl)-2-naphthamide (CENA) or N-(2-bromoethyl)-2-naphthamide (BENA), a ring-expanded isomer of 2-(2-naphthyl)-2-oxazoline (NOz) and the NAz