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This article reports on the reaction of 2-hetaryl-2-(furanyl-2-ylidene)acetonitriles with aromatic amines as N-nucleophiles. 2-Hetaryl-2-(furanyl-2-ylidene)acetonitriles represent versatile building blocks in syntheses of ω-(N-aryl)alkyl substituted heterocycles due to the presence of 1,3-bielectrophilic acrylonitrile fragment functionalized with unsaturated heterocyclic ring and nucleophilic azaheterocyclic moiety. The carbonyl group masked within the N-arylpyrrolidinylidene fragment which undergoes a ring opening through the reaction with nucleophiles. So, a method for the synthesis of 2-hetaryl-6-hydroxy-3-(arylamino)hex-2-enenitriles and 2-hetaryl-2-(N-arylpyrrolidin-2-ylidene)acetonitriles has been developed by us. The proposed scheme is based on the available reagents using. As a result of Michael addition, the aromatic amines to 2-hetaryl-2-(furanyl-2-ylidene)acetonitriles followed by ring transformations has formed two types of products, depending on the reaction conditions. The reaction of substituted furanylylideneacetonitriles with aromatic amines proceeds in good to high yields affording the corresponding 3-(arylamino)hex-2-enenitriles and 2-(N-arylpyrrolidin-2-ylidene)acetonitriles derivatives. The stereochemistry of the ring-opening reaction follows the rules of a classical SN2 mechanism. The resulting linear products can be cyclized to 2-hetaryl-2-(furanyl-2-ylidene)acetonitriles in high yields by treatment with the catalytic amount of acid or the equimolar amount of aromatic amines. Under these conditions 2-hetaryl-6-hydroxy-3-(arylamino)hex-2-enenitriles arising from reaction gives the ring closure. Since both ring-opening and cyclisation occur with fixed stereochemistry the reaction appears a valuable modification to the preparation of acetonitriles derivatives.

The photoconductive and photovoltaic properties of fi lm composites based on the new oligomer polyepoxypropylpyridobenzothiazole were compared with the known poly-N-epoxypropylcarbazole, which contains the squarylium dye as a photoconductivity sensitizer. It was found that these composites have hole-type photoconductivity, and the internal photoelectric effect is determined by the photogeneration of charge carriers from dye molecules and by transport of the holes along the donor fragments of the polymer matrix. The photoconductivity and photovoltaic response increase in the transition to the new oligomer with the more effi cient conjugation system in the donor fragments.

It was found that film composites of the copolymer of styrene with octyl methacrylate with additions of the monomers of pyrido[2,1-b]benzothiazole derivatives have hole-type photoconductivity while the internal photoelectric effect in this medium is determined by the photogeneration of charge carriers from the monomers and transfer of nonequilibrium charge carriers through these monomers. In transition to a monomer with a more efficient conjugation system the photoconductivity and photovoltaic response are increased.

The photovoltaic and photoconductive properties of film composites of a copolymer of styrene with octyl methacrylate and additions of the monomer (Z)-2-(4-methylthiazol-2-yl)-2-(pyrrolidin-2-ylidene)acetonitrile (HL) and complexes of NiL2, CoL2, and CuL2 were investigated. It was established that these composites have hole-type photoconductivity while the inner photoeffect is determined by photogeneration of charge carriers from the HL monomers and by transport of nonequilibrium charge carriers among these monomers. The photovoltaic response increases with the metal complexes in the following order: CuL2, NiL2, CoL2.

The reactions of 2-(2-hetaryl)-2-(tetrahydrofuran-2-ylidene)acetonitriles with conformationally rigid and heterocyclic tertiary amines were investigated. Compounds with bipolar structures were obtained: 1-cyano-1-(2-hetaryl)-5-(pyridinium-1-yl)-1-penten-2-olates and 5-(4-aza-1-azoniobicyclo[2.2.2]oct-1-yl)-1-cyano-1-(2-hetaryl)pent-1-en-2-olates.

The reaction of 2-hetaryl-2-(tetrahydrofuran-2-ylidene)acetonitriles and 6-chloro-2-(2-hetarylidene)-3-oxohexanenitriles with amines was studied. It was shown that the reaction of primary aliphatic amines with 6-chloro-2-(2-hetarylidene)-3-oxohexanenitriles takes place through a stage involving the formation of 2-hetaryl-2-(tetrahydrofuran-2-ylidene)acetonitriles followed by opening of the furanylidene fragment of the latter and the formation of 2-(2-hetaryl)-6-hydroxy-3-(R-amino)-2-hexenenitriles.

The reaction of azolylacetonitriles with γ-chlorobutyryl chlorides gave the corresponding 2-(1-R-1,3-di- hydro-2H-benzimidazol-2-ylidene)-, 2-(1,3-benzothiazol-2-ylidene)-, and 6-chloro-2-(4-methylthiazol-2-ylidene)-3-oxohexanenitriles. A study of the intramolecular cyclization of 2-(quinazolin-2-ylidene)-3-oxo-6-hexanenitriles and -heptanenitriles has led to the development of an efficient method for the preparation of 2-(quinazolin-2-yl)-2-(tetrahydrofuran-2-ylidene)acetonitriles. The (Z,E)-isomerism of the synthesized 2-hetaryl-2-(tetrahydrofuran-2-ylidene)acetonitriles was studied.

A new method has been developed for the synthesis of 4,5-dihydro-1,4-benzothazepin-3(2H)ones derivatives by the acylation of N-substituted 2-chloro-5-nitrobenzylamines with acetylmercaptoacetyl chloride and α-acetylmercaptopropionyl chloride with subsequent removal of the S-acetyl protecting group and intramolecular nucleophilic substitution. The oxidation of 4,5-dihydro-1,4-benzothiazepin-3(2H)-ones to the corresponding 1,1-dioxides has been investigated.

Published data on the synthesis and chemical properties of dihydrothiophen-3(2H)-one 1,1-dioxide, dihydro-2H-thiopyran-3(4H)-one 1,1-dioxide, 1-benzothiophen-3(2H)-one 1,1-dioxide, and 1H-isothio-chromen-4(3H)-one 2,2-dioxide are reviewed. The choice of subjects was based on the presence of identical structural fragments, carbonyl, active methylene, and sulfonyl groups.

The reaction of 2-hetaryl-2-(tetrahydro-2-furanylidene)acetonitriles with a electrophilic reagent (anisaldehyde) was studied. It was shown that condensation of the latter with 2-(4-oxo-3,4-dihydro-2-quinazolyl)- and 2-(1H-benzo[d]imidazol-2-yl)-2-(tetrahydro-2-furanylidene)acetonitriles in the presence of secondary amines or acids takes place with elimination of the furan fragment and the formation of 3-aryl-2-(4-oxo-3,4-dihydro-2-quinazolinyl)- and 2-(1H-benzo[d]imidazol-2-yl)acrylo-nitriles.

Acylation of hetarylacetonitriles and hetarylylideneacetonitriles with acetylmercaptoacetyl chloride gave 3-cyano-3-hetarylylidene-2-oxopropyl ethanethioates. 2-Amino-3-hetaryl-4(5H)oxothio-phenes or 2-hetarylylidene-3-oxo-4-sulfanylbutanenitriles were obtained on treating them with bases. Acylation of hetarylacetonitriles with 3-acetylmercaptopropionyl chloride gave 4-cyano-4-hetaryl-ylidene-3-oxobutyl ethanethioates, deacetylation of which gave 2-hetarylylidene-3-oxo-5-sulfanyl-pentanenitriles.

3-Pyrimidinylcoumarins have been synthesized by interacting 2- and 4-pyrimidinylacetonitriles with substituted salicylic aldehydes, but 9-pyrimidinylpyrano[2,3-f]chromene-4,8-diones were obtained with 8-formyl-7-hydroxychromones. Modification of the corresponding 7-hydroxycoumarins was carried out by acylation and aminomethylation.

The interaction of 2-chloroquinoline-3-carbaldehydes with 1H-benzimidazol-2-ylacetonitriles and 1-benzyl-1H-imidazol-2-ylacetonitrile has been studied. It was shown that products of condensation at the methylene group are formed under mild conditions. Carrying out the reaction under more forcing conditions leads to an intramolecular nucleophilic substitution of the chlorine atom and the formation of cyclic ionic compounds (in the case of N-substituted hetarylacetonitriles), which are subsequently dealkylated.

2-Cyanomethyl derivatives were obtained of imidazo[1,2-a]pyridine, imidazo[1,2-a]pyrimidine, and imidazo[2,1-b]thiazole, and their reactivity was investigated by an example of imidazo[1,2-a]pyridine: It was subjected to nitration, bromination, azo coupling and nitrosation. Acylation of the methylene group effected by amino acids esters with a subsequent addition of the amino group to the cyano group resulted in the formation of 5-amino-4-imidazo[1,2-a]-pyridin-2-yl-1-phenyl-1,2-dihydro-3H-pyrrol-3-one and 2-amino-1-ethyl-3-imidazol[1,2-a]pyridin-2-yl-4(1H)-quinolinone.

The reaction of 4-oxo-3,4-dihydroquinazolyl-and benzimidazolylacetonitriles with 2-chloro-2-quinolinecarbaldehydes and 1-aryl-5-chloro-3-methyl-1H-pyrazole-4-carbaldehydes gave the corresponding 3-(2-chloro-3-quinolyl)-2-(4-oxo-3,4-dihydro-2-quinazolyl)-2-propenenitriles and 3-(1-aryl-5-chloro-3-methyl-1H-4-pyrazolyl)-2-hetaryl-2-propenenitriles. Intramolecular cyclization of these compounds gives 15-oxo-15H-benzo[6,7][1,8]naphthyridino[2,1-b]quinazoline-6-carbonitriles, 1-aryl-3-methyl-11-oxo-1,11-dihydropyrazolo[4′,3′:5,6]pyrido[2,1-b]quinazoline-5-carbonitriles, and 1-aryl-3-methyl-1H-benzo[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyridine-5-carbonitriles.

3-Cyano-3-hetaryl-2-oxopropyl-and 3-cyano-3-hetaryl-1-methyl-2-oxopropyl ethanethioates were obtained by the acylation of 2-azahetarylacetonitriles with (acetylthio)acetyl and α-(acetylthio)propionyl chlorides respectively. They are deacetylated by the action of amines and undergo cyclization with the formation of 5-amino-4-hetarylthiophen-2(2H)-ones.

3-Cyano-3-hetaryl-2-oxopropyl thioacetates were obtained by the acylation of hetarylacetonitriles with acetylmercaptoacetyl chloride. Their reaction with amines led to the formation of 2-amino-3-hetaryl-4(H)-oxothiophenes.

A new method is proposed for the synthesis of 2-amino-4(5H)-oxothiophenes with aryl and hetaryl substituents in position 3 of the molecule by the acylation of aryl- and 2-azahetarylacetonitriles with mercaptoacetic acid ethyl ester.

2-Hetaryl-3-oxo-4-phthalimidobutyronitriles (and pentanonitriles) were obtained with high yields by C-acylation of hetarylacetonitriles with N-phthaloylglycine and α-alanine chlorides respectively under the conditions of base catalysis. Hydrazinolysis of the phthaloyl protection in these compounds leads to the formation of 5-amino-4-hetaryl-2,3-dihydro-1H-3-pyrrolones.

The interaction of 4-oxo-3,4-dihydroquinazolinyl- and benzimidazolylacetonitriles with 2,6-dihalobenzaldehydes leads to 3-(2,6-dihalophenyl)-2-(4-oxo-3,4-dihydro-2-quinazolinyl)acrylonitriles and 2-(1H-benzo[d]imidazol-2-yl)-3-(2,6-dihalophenyl)acrylonitriles respectively. As a result of intramolecular cyclization of these nitriles 4-halo-12-oxo-12H-quino[2,1-b]quinazoline-6-carbonitriles and 4-halobenzo[4,5]imidazo[1,2-a]quinoline-6-carbonitriles respectively are formed.

Reactions of 3,4-dichloro-N-R-maleimides with substituted thiouracils at 40°C gave a 1:1 mixture of isomers of pyrrolothiazolopyrimidinetriones. Under conditions of thermodynamic control (100°C, 5 h) only pyrrolo[3',4':4,5]thiazolo[3,2-a]pyrimidine-4,6,8-triones were formed, hydrolysis of which followed by decarboxylation gave 5-oxo-5H-thiazolo[3,2-a]pyrimidine-2-carboxamide. The structure of N2-phenyl-6-methyl-5-oxo-5H-thiazolo[3,2-a]pyrimidine-2-carboxamide was confirmed by X-ray crystallography. Analogous cyclization of 3,4-dichloro-N-R-maleimides with 2-thioxoquinazol-4-one also gave a mixture of two isomers which were successfully separated by fractional crystallization.

Reactions of 2-hetarylacetonitriles 1 with ethyl 2-alkylsulfanyl-4-chloro-5-pyrimidinecarboxylates 4 were studied. The interaction of pyridine, benzimidazole and benzothiazole derivatives 1a–d affords a series of new condensed pyridopyrimidines 5–7 . In the case of benzoxazole- and 4-arylthiazole derivatives 1e–h ethyl 4-[(2-hetaryl)-cyano-methyl]-2-alkylsulfanylpyrimidine-5-carboxylates 9a–f were formed. Reactions of quinazoline derivatives 1i,k afford stable intermediates 9h,i which formed the cyclic compound 12 of angular structure in the presence of potash. The influence of the basicity of heterocycles and of steric factors on the intramolecular acylation reaction was studied.

2-(4-Oxo-3,4-dihydro-2-quinazolinyl)acetonitriles have been obtained by the interaction of α-cyanoethylthioiminoacetate with substituted anthranilic acids. Prototropy became apparent in the series of synthesized compounds. Reactions of the 2-(4-oxo-3,4-dihydro-2-quinazolinyl)acetonitriles have been carried out with (hetero)aromatic aldehydes leading to the formation of 3-aryl-2-(4-oxo-3,4-dihydro-2-quinazolinyl)acrylonitriles.

A convenient method has been developed for the synthesis of 3-hetaryl-1,2,4,5-tetrahydropyrrolo[1,2-a]quinazoline-2,5-diones by the interaction of 4-chloro-2-hetaryl-3-oxobutyronitriles with substituted anthranilic acids.

We have established that when 5-chloro-6-[cyano(2,3-dihydro-1-R-benzo[d]azol-2-yl)methyl]-2,3-pyrazinedicarbonitriles are reacted with nucleophilic reagents (aliphatic and aromatic amines, hydrogen sulfide), annelation of the five-membered ring occurs on the [b] face of the pyrazine with formation of 6-amino-7-hetaryl-5-R-5H-pyrrolo[2,3-b]pyrazine-2,3-dicarbonitriles and 6-amino-7-(1H-benzo[d]imidazol-2-yl)thieno[2,3-b]pyrazine-2,3-dicarbonitrile respectively. Further heating with excess of acylating reagent leads to formation of a novel heterocyclic system 1H-benzo[4,5]imidazo[1,2-c]pyrazino[2',3':4,5]pyrrolo[3,2-e]pyrimidine. Reaction of vicinal dinitriles with hydrazine hydrate leads to the novel system 1H-pyrrolo[2',3':5,6]pyrazino[2,3-d]pyridazine.

It has been found that malonodinitrile and 2-(6-R1-oxo-3,4-dihydro-2-quinazolyl)acetonitrile in the presence of triethylamine undergo hetarylation by 5,6-dichloro-2,3-pyrazinedicarbonitrile at the active methylene group to give the triethylammonium salt of 2-(3-chloro-5,6-dicyano-2-pyrazinyl)malononitrile or 5-chloro-6-cyano(6-R1-4-oxo-1,2,3,4-tetrahydro-2-quinazolylidene)methyl-2,3-pyrazinedicarbonitriles. Reaction of these with primary amines leads to annelation of the pyrrole ring at the pyrazine [b] edge to give 6-amino-5-R-5H-pyrrolo[2,3-b]pyrazine-2,3,7-tricarbonitriles and 6-amino-5-R2-7-(6-R1-4-oxo-3,4-dihydro-2-quinazolyl)-5H-pyrrolo[2,3-b]pyrazine-2,3-dicarbonitriles respectively.

Bromination of 1-oxo(imino, amino)benzo[4,5]imidazo[1,2-a]pyridines gave the corresponding 2-bromo derivatives. Acylation using the Vilsmeier complex in acetic anhydride gave the N-formyl and N-acetyl derivatives. The reaction of the amine with the Vilsmeier complex, acetyl acetone, ethyl acetoacetate, and 2,5-dimethoxytetrahydrofuran occurs at the amino group.

Reactions of 2-(4-aryl-1,3-thiazol-2-yl)-3-oxo-4-chlorobutyronitriles with primary aromatic amines result in nucleophilic substitution of the chlorine atom by amino group, followed by intramolecular addition of the secondary amino group to the cyano group. The products are 5-amino-1-aryl-4-(4-aryl-1,3-thiazol-2-yl)- 2,3-dihydro-1H-pyrrol-3-ones which are structurally related to the known antiischemic drugs.

The reaction of 2-(2-azahetaryl)-3-oxo-4-chlorobutyronitriles with substituted benzaldehyde hydrazones gives 4-arylideneamino-2-(1-R-benzimidazol-2-yl)-3-oxobutyronitriles, the structures of which were proved using spectroscopic data, the results of elemental analysis, and through their chemical reactions. It was found that the reaction course depends on the basicity of the heterocyclic fragment in the starting nitrile. A likely mechanism for the process is proposed.

A new method is proposed for the synthesis of 2-amino-6-nitroindoles, based on the reaction of 2-haloanilines and substituted acetonitriles. The reaction of 2-amino-6-nitroindoles with β-dicarbonyl compounds was studied.

We have obtained 2-(4-arylthiazol-2-yl)-4-chloro-3-oxobutyronitriles by acylation of 4-aryl-2-cyanomethylthiazoles with α-chloroacetyl chloride. We have studied their reaction with secondary aliphatic amines, leading to formation of 4-dialkylamino-2-(4-arylthiazol-2-yl)-3-oxobutyronitriles, and also intramolecular alkylation with formation of 3-aryl-7-cyano-6(5H)-oxopyrrolo[2,1-b]thiazoles. We have determined some aspects of the tautomerism of the synthesized compounds.

The reaction of 2-(2-azahetaryl)-3-oxo-4-chlorobutane nitriles with esters of aromatic acids was studied. A series of 1H,4H-3-(2-azahetaryl)pyrrolo[1,2-a] quinazoline-2,5-diones and 1-aryl-2-amino-3-(2-azahetaryl)-4-(5H)-oxopyrroles was obtained. The reaction of the latter with hydrazine and acetic anhydride was investigated.

Reaction of 2,3-dichloro-5,6-dicyanopyrazine with α-azahetarylacetonitriles gives α-(3-chloro-5,6-dicyanopyrazin-2-yl)-α-(2-azahetaryl)acetonitriles. Subsequent heating in pyridine causes an intramolecular cyclization to yield condensed pyrrolo[b]pyrazines.

α-(2-Methylsulfonyl-5-chloropyrimidinoyl-4)-2-azahetarylacetonitriles were prepared by the reaction of 2-methylsulfonyl-5-chloropyrimidine-4-carboxylic acid chloride with 2-cyanomethylazaheterocycles.

A study has been made of the interaction of 2-[2-(benz)azolyl]3-keto-4-chlorobutanenitriles with primary aliphatic amines. This is a convenient method for the synthesis of 2-amino-3-[2-(benz)azolyl]-4(5H)-ketopyrroles.

The reactions of 2-(2-hetaryl)-2-(tetrahydrofuran-2-ylidene)acetonitriles with conformationally rigid and heterocyclic tertiary amines were investigated. Compounds with bipolar structures were obtained: 1-cyano-1-(2-hetaryl)-5-(pyridinium-1-yl)-1-penten-2-olates and 5-(4-aza-1-azoniobicyclo[2.2.2]oct-1-yl)-1-cyano-1-(2-hetaryl)pent-1-en-2-olates.

The method of synthesis of 1-(triethylsilyl)-3-[4-(hetaryl)phenyl]-5-(trimethylsilyl)penta-1,4-diyn-3-ols based on the interaction between 1-(triethylsilyl)-5-(trimethylsilyl)penta-1,4-diyn-3-one and lithium derivatives of 1-(4-bromophenyl)-1H-indole or 9-(4-bromophenyl)-9H-carbazole has been developed., Разработан метод синтеза 1-(триэтилсилил)-3-[4-(гетарил)фенил]-5-(триметилсилил)пента-1,4-диин-3-олов, основанный на взаимодействии литиевых производных 1-(4-бромфенил)-1Н-индола и 9-(4-бромфенил)-9Н-карбазола с 1-(триэтилсилил)-5-(триметилсилил)пента-1,4-диин-3-оном., Розроблено метод синтезу 1-(триетилсиліл)-3-[4-(гетарил)феніл]-5-(триметилсиліл)пента-1,4-діїн-3-олів, що базується на взаємодії літієвих похідних 1-(4-бромофеніл)-1Н-індолу та 9-(4-бромофеніл)-9Н-карбазолу з 1-(триетилсиліл)-5-(триметилсиліл)пента-1,4-діїн-3-оном.

6,7,8,9-Tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepin-3-ylacetonitrile reacts with carboxylic acid anhydrides and chlorides to afford acylation products at the nitrogen atom in the heteroring or methylene carbon atom, depending on the conditions and nature of the acylating agent. Heating of the N-acyl derivatives leads to migration of the acyl group with formation of C-acyl derivatives.

The acylation of 3-amino-4-cyano-1(2H)isoquinolines with benzoyl chloride leading to the formation of 1,3 oxazino[4,5-clisoquinoline-6-ones has been studied. Previously undescribed 1-aminopyrimido[4,5-cJisoquinolirt 6-ones have been obtained by the reaction of the appopriate 3-amino-](2H)isoginolones with formamide. Nucleophilic replacement has been carried out with 3-amino-1-chloroisoquinoline by the action of sodium hydroxide, primary alcohols, hydrazine hydrate, and various amines. 1,2,4-Triazino[2,3-b]isoginolone has been synthesized by condensing 2,3-diamino-1 (2H)isoquinolone with mesoxalic acid ethyl ester.

The interaction of α-substituted 2-(3-chloro)quinoxalylacetonitriles with azines to give condensed indolizino [2,3-b]quinoxalines has been studied. A mechanism for the reaction has been proposed which includes an intramolecular vicarious substitution of hydrogen in the azolium salt nucleus. The limits of utility of the reaction have been determined and some chemical properties of the compounds synthesized have been studied.

The reaction of α-substituted 2-quinoxalylacetonitriles with 1-alkyl(aryl)imidazoles, -benzimidazoles, -1,2,4-triazoles and 5,6-dihydroimidazo[i,j]quinoline was studied. It was found that during the course of the reaction an unusually easy dealkylation of the azole ring takes place, while the aryl substituent is not split off. A reaction mechanism has been proposed including the formation of an ylide intermediate, followed by subsequent electrophilic attack on the C(2) position of the azolium ring. The applicability boundaries of the reaction studied and the spectral characteristics of the synthesized compounds were investigated.

3-Amino-4-aryl-1(2H)-isoquinolones have been synthesized by treating 2-halobenzamides with arylacetonitriles. The angle of rotation of the 4-phenyl grop has been determined.