反应详情

Repeating the procedure of Step D of Example 1, but using in place of the 2-bromomethyl-4-chlorophenylisocyanate used therein, an approximately equal amount of 2-bromomethyl-5-chlorophenylisocyanate, there is accordingly obtained 7-chloro-2-dimethylamino-4H-1,3-benzoxazine hydrobromide (m.p. 173°-176°) which is converted to its free base form (m.p. 118°-120°) in the same manner as described in Step D of Example 1.