P. M. Lukin

6,6-Dimethyl-4,8-dioxospiro[2.5]octane-1,1,2,2-tetracarbonitrile in the synthesis of heterocyclic compounds of the 2,3-dihydrofuran and 5,6,7,8-tetrahydro-4h-chromene series

Abstract6,6-Dimethyl-4,8-dioxospiro[2.5]octane-1,1,2,2-tetracarbonitrile (III), synthesized by the interaction of tetracyanoethylene with 2-bromo-5,5-dimethyl-1,3-cyclohexanedione, reacts with alcohols and ketoximes to form 2-alkoxy-2-(3-alkoxycarbonyl-2,2-dimethylpropyl)-5-amino-3-dicyanomethylene-4-cyano-2,3-dihydrofurans and 2-alkylidenaminoxy-2-(3-alkylidenaminoxycarbonyl-2,2-dimethylpropyl)-5-amino-3-dicyanomethylene-4-cyano-2,3-dihydrofurans. Compound III with triarylphosphines forms 2-(triarylphosphoranilidenamino)-7,7-dimethyl-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3,4,4-tricarbonitriles.

Synthesis of pyrrolopyrimidines from 2,5-diaryl-3,3,4,4-tetracyanopyrrolidines

Feasibility has been demonstrated for the synthesis of pyrrolo[1,2-a]pyrimidines by the reaction of 2,5-diaryl-3,3,4,4-tetracyanopyrrolidines I with β-dicarbonyl compounds, which was carried out by the rearrangement of I to give 2-(N-arylidenamino)-5-aryl-3,4-dicaynopyrroles II. A different pathway was found for the reaction of pyrroles II with β-diketones and ethyl acetoacetate. The existence of a latento-enaminonitrile fragment in these compounds permits their conversion to pyrrolo[2,3-d]pyrimidines.

Reaction of 4-oxoalkane-1,1,2,2-tetracarbonitriles with 1,3,5-trlaryl-2,4-diaza-1,4-pentadienes

Abstract2-Aryl-1,2,3,4-tetrahydropyridine-3,3,4,4,-tetracarbonitriles and 1,3,5-triaryl-9-oxo-1,2,3,4b,5,6,8a,9-octahydropyrido[3′,4′:3,4]pyrrolo[1,2-a][1,3,5]triazine-4b,8a-dicarbonitriles are formed by the reaction of 4-oxoalkane-1,1,2,2-tetracarnonitriles with 1,3,5-triaryl-2,4-diaza-1,4-pentadienes depending on the solvent used.

Refinement of the structure of the products of the interaction of 4-oxoalkane-1,1,2,2-tetracarbonitriles with aldehydes

It has been established by x-ray structural analysis that on reacting 4-oxoalkane-1,1,2,2-tetracarbonitriles with aldehydes 6-imino-2,7-dioxabicyclo[3.2.1]octane-4,4,5-tricarbonitriles are formed and not 3-imino-2,6-dioxabicyclo[2,2,2] octane-4,8,8-tricarbonitriles as has been proposed.

The easy hydrolysis of hexacyanocyclopropane, ethyl 1,2,2,3,3-pentacyanocyclopropane-1-carboxylate, 1,2,2,3,3-pentacyanocyclopropane-1-carboxamide, andN,N-dimethyl-1,2,2,3,3-pentacyanocyclopropane-1-carboxamide tor-1,c-2,c-3-tricyanocyclopropane-t-carboxamide

Hydrolysis of hexacyanocyclopropane (1a), ethyl 1,2,2,3,3-pentacyanocyclopropane-1-carboxylate (1b), 1,2,2,3,3-pentacyanocylopropane-1-carboxamide (1c), andN,N-dimethyl-1,2,2,3,3-pentacyanocylopropane-1-carboxamide (1d) in 95% acetic acid yieldsr-1,c-2,c-3-tricyanocyclopropane-t-1-carboxamide (3). The structure of3 was proved by X-ray diffraction analysis.

1,1,2-TRICARBAMOYL-2-CYANOETHANE IN CONDENSATION PROCESSES WITH ALDEHYDES

Abstract5-Alkyl-2-amino-3, 4-dicarbamoyl-4-cyano-4, 5-dihydrofurans were synthesized by the reaction of 1,1, 2tricarbamoyl-2-cyanoethane with carbonyl compounds in the presence of catalytic amounts of triethylamine in an aqueous medium. The structure of the dihydrofuran (Vb) was proved by x-ray crystallographic investigation of a single crystal.

REACTIONS OF 3,3,4,4-TETRACYANOPYRROLIDINES WITH ALCOHOLS

It was established that on treatment with alkali, 2,5-disubstituted 3,3,4,4-tetracyanopyrrolidines react with primary alcohols to form 5-alkoxy-2-(N-arylidenamino)-3,4-dicyanopyrroles. Depending on the ratio of the initial reagents, another reaction route is possible, leading to 6-alkoxy-4-amino-2-R-3-CH2R-5-cyano-3H-pyrrolo[2,3-d]pyrimidines. The effect of substituents on the reaction pathways is examined.

Chemistry of 1,1,2,2-tetracyanoethane. 11. Synthesis and stereochemical characteristics of 3-methyl-5-oxo-2′-amino-5′-phenyl -3′,4′,4′-tricyanoisoxazoline-4-spiro-1′-cyclopent-2′-ene

The Michael condensation of 1,1,2,2-tetracyanoethane with 3-methyl-4-benzylideneisoxazolin-5-one having the Z configuration leads to a heterocyclic spiran with retention of the cis orientation of the phenyl and keto groups. The deviations of the series of bond angles of the spiran from the standard values, the abnormal lengths of the C-C bonds adjacent to the gem-dicyano group, and the appearance of nonbonding >C=O(...)C≡N interactions and conjugation effects in the enaminonitrile fragment are discussed.

Synthesis of 2,12-diaryl-4-(arylmethyleneamino)-5,6,10,11,11-pentacyano-8-methyl-1,3,8-triazatricyclo[7,3,0,03,7]dodeca-4,6,9-trienes by the reaction of 2,5-diaryl-3,3,4,4-tetracyanopyrrolidines with diazomethane

Abstract2,12-Diaryl-4-(arylmethyleneamino)-8-methyl-5,6,10,11,11-pentacyano-1,3,8-triazatricyclo[7,3,0,03,7]dodeca-4,6,9-trienes (VIIa-c) are synthesized on methylation of 2,5-diaryl-3,3,4,4-tetracyanopyrrolidines with diazomethane in dioxan. Their structure was confirmed by an x-ray structural investigation of a single crystal of compound (VIIa).

Isomerization of 2-aryl-5,6-tetramethylene-3,3,4-tricyano-2,3,4,5-tetrahydropyridine-4-carbox-amides under the influence of acids

When 2-aryl-5,6-tetramethylene-3,3,4-tricyano-2,3,4,5-tetrahydropyridine-4-carboxamides are subjected to the action of acids, they are isomerized, forming either 2-aryl-5,6-tetramethylene-3,3,4-tricyano-1,2,3,4-tetrahydropyridine-4-carboxamides or 3-aryl-1,8-tetramethylene-6-oxo-2,7-diazobicyclo[3.2.1]octane-4,4,5-tricarbonitriles.