M. Yu. Krysin

Cascade Two- and Three-Component Cyclization Reactions Using 1,2-Diamino-4-Phenylimidazole and Cyclohexane-1,3-Diones

The reaction of 1,2-diamino-4-phenylimidazole with 5,5-R,R1-cyclohexane-1,3-diones and with the dimethyl formamide dimethyl acetal or triethyl orthoformate gives 7,7-R,R1-3-amino-1-phenyl-7,8-di-hydroimidazo[1,5-b]cinnolin-9(6H)-ones in good yield. These products may also be obtained from 1,2-diamino-4-phenylimidazole and 5,5-R,R1-(phenylaminomethylidene)cyclohexane-1,3-diones.

6-(1,3-Dioxoindan-2-ylidenemethyl)-1,2,2,4-tetramethyl-1,2-dihydro- and 1,2,3,4-Tetrahydroquinolines

Abstract6-Formyl-1,2,2,4-tetraalkyldi- and -tetrahydroquinolines have been synthesized by the Vilsmeier reaction and they are readily condensed with 1,3-indanedione to give 2-hetarylidene-1,3-indanediones. The latter exist as complexes with charge transfer from the quinoid structure of the heterocyclic fragment.

Synthesis of polyazaheterocycles containing linearly bound 1,2,4-thiadiazole using enaminones

A reaction of N-substituted 5-amino-3-(2-oxopropyl)-1,2,4-thiadiazoles with dimethylformamide dimethyl acetal gave 3-(5-amino-1,2,4-thiadiazol-3-yl)-4-(dimethylamino)but-3en-2-ones, whose cyclization with hydrazine, guanidine, 1H-pyrazol-5-amines and 6-aminopyrimidin-4(3H)-ones led to 3-methyl-1H-pyrazole, 4-methylpyrimidin-2-amine, 5-methyl3-arylpyrazolo[1,5-a]pyrimidines, and 5-methyl-2-R-pyrido[2,3-d]pyrimidin-4(3H)-ones containing a 5-amino-1,2,4-thiadiazole fragment linearly bound at position 3.

New Method for Synthesis of the Hetero-Cyclic System – 1,2,3,4-Tetrahydro-Imidazo[5,1-f][1,2,4]Triazin-7-Amine

Imidazotriazines are used as dyes, luminophores, and corrosion inhibitors [1, 2]. Earlier these compounds were obtained on the basis of diaminopyridinium salts, and this was not economically feasible. We decided to study an alternative method for the preparation of imidazotriazines starting from 1,2-diaminoimidazoles. In the course of the investigations we found that 1,2,3,4-tetrahydroimidazo[5,1-f][1,2,4]triazin-7-amines 4a-e are formed during the reaction of 1,2-diaminoimidazoles 1a-c, obtained by the reaction between benzaldehyde guanylhydrazones and halo ketones [1], with formaldehyde and primary amines 2a,b.

Spiro epoxy ketones. 2. Thermal transformations of 2-benzylideneindan-1,3-dione?-oxide

Abstract2-Phenyl-3,3,4,4-diphthaloyloxetane is formed when solutions of 2-benzylideneindan-1,3-dione α-oxide in benzene or carbon tetrachloride are heated, while 5-oxo-3-phenyl-2,2-phthaloyl-2,3-dihydroindeno[2,3-b][1,4]dioxine is formed when solutions in dioxane are heated.

1,3-Dipolar cycloaddition of 2-benzylideneindan-1,3-dione α-oxide to olefins

A carbonyl ylid, which reacts with maleic anhydride, N-phenylmaleinimide, and Β-nitrostyrene to form adducts resulting from 1,3-dipolar cycloaddition, is formed reversibly when 2-benzylideneindan-1,3-dione α-oxide is heated (80‡C). The reaction proceeds regio- and stereospecifically.