An isomerization–ring-closing metathesis (RCM) strategy afforded N-substituted 4H-1, 4- benzoxazines from the protected N-allyl-2-(allyloxy) anilines. In addition, RCM was used to synthesize the N-substituted, 8-membered benzo-fused heterocycles from the respective diallyl compounds: 1, 2, 5, 6-tetrahydro-1, 6-benzodiazocine, 5, 6-dihydro-2H-1, 6- benzoxazocine, 5, 6, 9, 10-tetrahydropyrido [2, 3-b][1, 4] diazocine and 5, 6-dihydro-2H-1, ...