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Mannich reaction of 1,3-indandione-1-phenylhydrazone (1) or 1,3-diphenylhydrazone (5) with morpholine or piperazine gave the Mannich base-phenylhydrazone 2 and 3 or the diphenylhydrazone 6 and 7, respectively. Whereas, such reaction with 1 or 5 using primary amines afforded the indeno[2,1-ƒ]-1,2,4-triazepin-6(2H)-one (4) or its 6-phenylhydrazone (8), respectively. Treatment of 5 with ammonium acetate and formalin afforded 9. The indeno[1,2-ƒ]-1,2,4,5- tetrazepin-10(2H)-one (11) was obtained from the 1,2-diphenylhydrazone 10 and formaldehyde.

When β-keto-ester1 a was reacted with dimethyl acetylenedicarboxylate ring expansion occurred to give substituted cyclooctadienones.Michael reactions of the title compounds1 with unsaturated ketones gave adducts, some of which underwent further cyclization reactions. A new route to α-tetralone ring system10 via cyclization of the intermediateMichael adduct9 is described.