A. N. Lyshchikov

Heterocyclization of michael adducts of β-diketones with arylmethylidene derivatives of malononitrile dimers

Reaction of arylmethylidene derivatives of malononitrile dimer with 1,3-cyclohexanediones in anhydrous methanol in the presence of sodium methylate as catalyst affords 4-amino-5-aryl-2-methoxy-6-oxo-5,6,7,8,9,10-hexahydrobenzo[b][1,8]naphthyridine-3-carbonitrile. In the presence of strong electron-donor substituents in the benzene ring the reaction takes another route resulting in 4-amino-2-aryl-6-methoxypyridine-3,5-dicarbonitriles.

Synthesis of Alkyl 5,6-Dialkyl-2-amino-3-cyanopyridine-4-carboxylates

An unusual route has been found for the hydrolysis of 3-amino-1,1-dialkoxy-6,7-dialkyl-4-aryl-3a,4,5,7a-tetrahydro-1H-pyrrolo[3,4-c]pyridine-3a,7a-dicarbonitriles in acidic medium which leads to the formation of alkyl 5,6-dialkyl-2-amino-3-cyanopyridine-4-carboxylates.

Interaction of Alkyl 5,6-Dialkyl-2-amino-3-cyano-4-pyridinecarboxylates with O-Nucleophiles. Synthesis of 6,7-Dialkyl-4-amino-2,3-dihydro-1H-pyrrolo[3,4-c]pyridine-1,3-diones

The reaction of alkyl 5,6-dialkyl-2-amino-3-cyano-4-pyridinecarboxylates with certain O-nucleophiles was investigated, as a result of which 6,7-dialkyl-4-amino-2,3-dihydro-1H-pyrrolo[3,4-c]pyridine-1,3-diones were synthesized.

Reduction of Alkyl-2-amino-5,6-dialkyl-3-cyanopyridine-4-carboxylates

Reduction of alkyl-2-amino-5,6-dialkyl-3-cyanopyridine-4-carboxylates with sodium borohydride in protic solvents gave rise to 4-amino-3-imino-6,7-dialkyl-1,3-dihydrofuro[3,4-c]pyridines that at hydrolysis in acid medium afforded the corresponding lactones.

Three-component synthesis of 2-(4-amino-2,5-dihydro-1H-imidazol-5-ylidene)malononitriles

Abstract2-(4-Amino-2,5-dihydro-1H-imidazol-4-ylidene)malononitriles were synthesized by three-component reaction of tetracyanoethylene, carbonyl compound, and ammonium acetate. The synthesis can be performed in two steps with intermediate isolation of 2-aminoethene-1,1,2-tricarbonitrile, as well as using preliminarily prepard 2-aminoethene-1,1,2-tricarbonitrile and 1,3,5-trisubstituted 2,4-diazapentadienes.

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.

Alkyl 2-amino-5,6-dialkyl-3-cyanopyridine-4-carboxylates in reactions with electrophilic reagents

In reaction of alkyl 2-amino-5,6-dialkyl-3-cyanopyridine-4-carboxylates with isocyanates formed unstable ureas, and with nitrous acid at 60–70°C alkyl 5,6-dialkyl-2-oxo-1,2-dihydro-4-pyidinecarboxylates were obtained. It was shown for the latter that their reactions with organic acids and amides occurred at the cyano group, and the alkaline hydrolysis involved the ester group.

Interaction of Methyl 5,6-Dialkyl-2-amino-3-cyanopyridine-4-carboxylates with Primary Amines

An unusual direction has been found for the interaction of alkyl 5,6-dialkyl-2-amino-3-cyanopyridine-4-carboxylates with primary amines leading to the formation of 2,6,7-trialkyl-4-amino-2,3-dihydro-1H-pyrrolo[3,4-c]pyridine-1,3-diones.

Synthesis of 3-Acetonyl-1,1,2,2-tetracyanocyclobutanes

1,1,2,2-Tetracyanocyclobutanes are most frequently synthesized by a [2+2]-cycloaddition reaction [134]. The most facile reaction occurs between tetracyanoethylene and alkenes whose double bond is activated by electron-donor substituents. 1,1,2,2-tetracyanocyclobutanes are considered to be formed by a nonconcerted cycloaddition reaction involving a zwitterionic intermediate. The reactions of tetracyanoethylene with styrene [5] and vinyl ether [6] are assigned to this type of reactions. It is shown that first a charge-transfer complex is formed. Further, say, in the reaction of tetracyanoethylene with styrene, the

Alkaline scission of a urea unit in 5-alkyl-2-amino-N-ureido-3,4-dicyanopyrroles

The scission of the urea group in 5-alkyl-2-amino-3,4-dicyano-N-ureidopyrroles on boiling in KOH solution in DMSO was observed to give 5-alkyl-1,2-diamino-3,4-dicyanopyrroles which were used for the synthesis of pyrrolo[1,2-b][1,2,4]triazepines by reaction with acetylacetone.