The synthesis of novel polycyclic heterocyclic ring systems via photocyclization. 21 . Naphtho[2′,1′:4,5]thieno[2,3-c]naphtho[1,2-f]-quinoline, naphtho[2′,1′:4,5]thieno[2,3-c]naphtho[1,2-f][1,2,4]-triazolo[4,3-a]quinoline and naphtho[2′,1′:4,5]thieno[2,3-c]naphtho[1,2-f]-tetrazolo[1,5-a]quinoline

Photocyclization of 3‐chloro‐N‐(3‐phenanthryl)naphtho[1,2‐b]thiophene‐2‐carboxamide (12) furnished only one of the two possible isomers, i.e., naphtho[2′,1′:4,5]thieno[2,3‐c]naphtho[1,2‐f]quinolin‐6(5H)‐one (13), which was further elaborated to yield the unsubstituted ring system 7, its triazole 8 and tetrazole 9. The structural confirmation of 7 was accomplished by the total assignment of its 1H and 13C nmr spectra utilizing the concerted two‐dimensional nmr spectroscopic experiments.