Reactions of quinoxaline with 3-methyl-1-phenylpyrazol-5-one

Quinoxaline during the reaction with 3-methyl-1-phenylpyrazol-5-one in the presence of triethylamine at room temperature in dimethylsulfoxide eliminates o-phenylenediamine and gives 4,4'-methylene-bis(3-methyl-1-phenylpyrazol-5-one) and 1,1,2,2-tetrakis(5-methyl-2-oxo-2-phenyl-1,2-dihydro-3H-pyrazol-4-yl)ethane. The latter was proved to be the intermediate to form the above dipyrazolylmethane derivative. © 2012 Mendeleev Communications. All rights reserved

Self condensation of enamines mediated by acetylation. A novel approach to 1-(azol-5-yl)-(1E,3Z)-butadiene-4-N,N-dimethylamines

Novel self-condensation of 3-(azol-5-yl)-1,1-dimethylenamines has been found to form new C-C bonds leading to 2,4-(1,2,3-triazole-1,2,3-thiadiazole-3- phenylisothiazole)-(1E,3Z)-5-yl-butadiene-1-amines. The discovered reaction represents a new example of C-H functionalization in unsaturated systems and can serve an efficient synthetic approach to rational design of new 2,4-(diazole-5-yl)-dieneamines. © 2012 The Royal Society of Chemistry