In cyclic 1,5-diketones the position of the carbonyl groups determines exclusively the ease of their cyclization and makes them as convenient basis for the synthesis of nitrogen-, oxygen-, and sulfur-containing heterocycles [1,2].The aim of the present work is the study of the reactivity of the Michael adducts 1a-j [3,4], obtained from dimedone and aromatic aldehydes or furfural (adduct 1j), in relation to the bidentatic nucleophiles o-phenylenediamine 2 and o-aminophenol 3. The cyclic tetraketones 1a-j exist in the enolic form which makes them structurally close to α,β-unsaturated ketones, the reactivity of which in relation to 1,4-dinucleophiles has been studied previously [5,6].The electronic character of the substituents in R influence the direction of the interaction of compounds 1a-i with o-phenylenediamine 2 on boiling these reactants in 2-propanol (method A). The corresponding hexahydrodibenzodiazepinones 4a-f were obtained from tetraketones 1a (R = Ph) and 1b-f (electronwithdrawing substituents in R: 4-F, 4-Cl, 4-Br, 4-NO 2 ).When electron-donating substituents (4-OMe, 4-NMe 2 , 2-OH) are present in R, as in compounds 1g-i, either decomposition of the latter takes place (in the case of tetraketones 1g,h) with the formation of the corresponding azomethines 5a,b, or conversion into decahydroacridinedione 6 occurs (from tetraketone 1i). Hexahydrodibenzodiazepinone 4j is obtained from hetaryl-substituted tetraketone 1j (R = 2-furyl).Tetraketones 1a-d,g,h do not react with o-aminophenol 3 under the conditions mentioned above (method A). Only on boiling these reactants in DMF the interaction products, decahydroacridinediones 7a-f, were obtained in good yield.The results obtained enable the interaction of compounds 1 with binucleophiles 2 and 3 to be represented in the following way.