Abstract The rates of detritiation of [2-T]-,[3-T]-, and [4-T]-1, 8-dimethylnaphthalene and the corresponding specifically labelled acenaphthenes and perinaphthanes have been measured at 30 in anhydrous trifluoroacetic acid. The order of ortho and para reactivities is acenaphthene> perinaphthane> 1, 8-dimethylnaphthalene; the meta positions are much less reactive in the order acenaphthene> 1, 8-dimethyl-naphthalene> perinaphthane. This ...