Synthesis and some reactions of functionalized benzo[b]azonines and Bi(benzo[b]azonines)

Tetrahydro-lf.-benzo[fo]azonin-2,7-dione (2a) has been used as a precursor in the synthesis of di-benzo[b,f][l,5]diazacyclododecene and dibenzo[b,g][l,6]diazacyclododecene ring systems 4 and 5, respectively, via periodate oxidation of the appropriate indolo-benzo[b]azonines 3 and 7. The synthesis of hexahydro-benzo[b][l,4]diazecin-2,7-dione (10) has been achieved by the Schmidt reaction of 2a. The periodate oxidation of 9,9'-methylenebis(2,3,4, 9-tetrahydro-lH-carbazole) (11) afforded 1,1'-methylenebis(3,4,5,6-tetrahydro- lH-benzo[b]azonin-2,7-dione) (12). Its 6,6'-methylenebis isomer 13 was obtained by treating 2a with formaldehyde. Oxidation of 16 gave the unsymmetrical bi(benzo[b]azonine) 17. The Mannich reaction of 2a led to a mixture of its 6-methylene derivative 19 and the spirocyclic system 20. The reactions of 2a with aldimines and aromatic aldehydes were also investigated.