Lysenko O. Synthesis of poly- and heterocyclic compounds based on N-substituted 1,4-benzoquinone monoimines

Change of NSO2Ar substituent by NC(O)X at the carbon atom of the quinoid nucleus leads to a decrease in the acceptor effect of the substituent on the double bonds of the quinoid nucleus, to the redistribution of the electronic density of the NBMO localization, and to the change of the diene attachment direction in the reaction of N-substituted 1,4-benzoquinone monoimines with 2,3-dimethyl-1,3-butadiene. Pyrazole derivatives forming in the reaction of 4-aminoantipyrine with N-chloro-1,4-benzoquinone monoimines and 1,4-benzoquinones by the 1,2-attachment–elimination mechanism. It is established that the synthesis of 1,3-benzoxathiol-2-one derivatives from N-substituted 1,4-benzoquinone monoimines is more effective with thiourea than with potassium thiocyanate. It is established that the direction of the reaction of N-substituted 1,4-benzoquinone monoimines with active methylene compounds depends from the reaction conditions, which allowed to develop methods of the benzofuran derivatives synthesis. We obtained N-carbamoyl-1,4-benzoquinone monoimines and their derivatives, for which Z,E-isomerization regarding to the C=N bond by inversion mechanism and the slow rotation around the NH–C(O) bond are observed. These quinone imines exhibit a dual character of reactivity: quinone imines form products by the 1,2-addition scheme, which, as a result of cyclization, are converted into heterocyclic compounds as urea derivatives in reaction with alcohols.