Electrophilic heterocyclization of 6-alken(yn)ylsulfanyl-pyrazolo[3,4-<Emphasis Type="Italic">d</Emphasis>]pyrimidin-4(5<Emphasis Type="Italic">H</Emphasis>)-ones

6-Allylsulfanyl-1-arylpyrazolo[3,4-d]pyrimidin-4(5H)-ones react with iodine and sulfuric acid to give angular pyrazolothiazolopyrimidine derivatives. The reaction of 6-(prop-2-yn-1-ylsulfanyl)-1-(4-tolyl)-pyrazolo[3,4-d]pyrimidin-4(5H)-one with sulfuric acid gives angularly fused pyrazolo[4,3-e][1,3]thiazolo-[3,2-a]pyrimidin-4-one, whereas in the reaction with sodium methoxide linearly fused pyrazolo[3,4-d][1,3]-thiazolo[3,2-a]pyrimidin-4-one was formed. Linearly fused pyrazolo[3′,4′:4,5]pyrimido[2,1-b][1,3]thiazole derivatives were also obtained by reaction of 1-aryl-6-(3-phenylprop-2-en-1-ylsulfanyl)pyrazolo[3,4-d]pyrimidin-4(5H)-ones with sulfuric acid.     

Fused Pyrimidine Systems: XVII. Imidazo- and Pyrimidopyrido[3,2-<Emphasis Type="Italic">d</Emphasis>]pyrimidin-4(3<Emphasis Type="Italic">H</Emphasis>)-ones

2-(Allylamino)pyrido[3,2-d]pyrimidin-4(3H)-one was converted to linearly fused dihydroimidazo- [1,2-a]pyrido[3,2-d]pyrimidine on heating in polyphosphoric acid, whereas its reactions with molecular iodine and chlorosulfanylarenes afforded mainly angularly fused analogs. 2-(Cinnamylamino)pyrido[3,2-d]pyrimidin- 4(3H)-one reacted with polyphosphoric acid and chlorosulfanylarenes to give linear pyrido[3,2-d]pyrimido-[1,2-a]pyrimidinones, and its iodocyclization led to the formation of angularly fused derivative.     

Reactions of 2-(2-propynylsulfanyl)-5,6,7,8-tetrahydrobenzo[<Emphasis Type="Italic">b</Emphasis>]thieno[2,3-<Emphasis Type="Italic">d</Emphasis>]pyrimidin-4(<Emphasis Type="Italic">3H</Emphasis>)-one with arylsulfenyl chlorides

2-(2-propynylsulfanyl)-5,6,7,8-tetrahydrobenzo[b]thieno[2,3-d]pyrimidin-4(3H)-one with arylsulfenyl chlorides in chloroform gave products of anti-Markownikoff Ad _E-addition. The use of nitromethane as solvent in the presence of lithium perchlorate additives favored intramolecular electrophilic cyclization into 1-arylsulfanyl-1,2,6,7,8,9-hexahydro-4H-benzo[4,5]thieno[3,2-e][1,3]thiazolo[3,2-a]-pyrimidin-5-one.     

Synthesis,S-alkylation,and fungicidal activity of 4-(benzylideneamino)thioglycolurils

A series of 1,3-disubstituted 4-benzylideneamino-5-thioxohexahydroimidazo[4,5-d]imidazol-2(1H)-ones (thioglycolurils) was synthesized via the reaction of 5,7-disubstituted 3-thioxoperhydroimidazo[4,5-e]-1,2,4-triazin-6-ones with hydroxy-, alkoxy-, and fluorocontaining benzaldehyde derivatives. An alkylation of the obtained thioglycolurils with methyl iodide or 4-bromobenzyl bromide provided the corresponding 6-benzylideneamino-5-alkylsulfanyl-3,3a,6,6a-tetrahydroimidazo[4,5-d]imidazol-2(1H)-ones. The fungicidal activity of some synthesized compounds against pathogens causing diseases of agricultural crops was studied.     

Iodocyclization of 2-[allyl(methallyl)sulfanyl]-6-(trifluoromethyl)pyrimidin-4(3<Emphasis Type="Italic">H</Emphasis>)-ones

Iodination of 2-[allyl(methallyl)sulfanyl]-6-(trifluoromethyl)pyrimidin-4(3H)-ones was accompanied by cyclization to 2,3-dihydro[1,3]thiazolo[3,2-a]pyrimidin-4-ium triiodides. 3-(Iodomethyl)-3-methyl- 7-oxo-5-(trifluoromethyl)-2,3-dihydro[1,3]thiazolo[3,2-a]pyrimidin-4-ium triiodide was reduced with sodium iodide to 3,3-dimethyl-7-oxo-5-(trifluoromethyl)-2,3-dihydro[1,3]thiazolo[3,2-a]pyrimidin-4-ium iodide.     

Synthesis of 5,8-Diamino-Substituted Pyrano[4″,3″:4′,5′]pyrido[3′,2′:4,5]thieno[3,2-<Emphasis Type="Italic">d</Emphasis>]pyrimidines and Pyrimido[4′,5′:4,5]thieno[2,3-<Emphasis Type="Italic">c</Emphasis>]isoquinolines

Ethyl 1-amino-8,8-dimethyl-5-(piperidin-1-yl)-8,9-dihydro-6H-pyrano[4,3-d]thieno[2,3-b]pyridine-2-carboxylate and ethyl 1-amino-5-(piperidin-1-yl)-6,7,8,9-tetrahydrothieno[2,3-c]isoquinoline-2-carboxylate reacted with benzoyl isothiocyanate to give the corresponding 1-thioureido derivatives which underwent cyclization to 2,2-dimethyl-5-(piperidin-1-yl)-10-thioxo-1,4,10,11-tetrahydro-2H-pyrano[4″,3″:4′,5′]pyrido-[3′,2′:4,5]thieno[3,2-d]pyrimidin-8(9H)-one and 5-(piperidin-1-yl)-10-thioxo-1,2,3,4,10,11-hexahydropyrimido-[4′,5′:4,5]thieno[2,3-c]isoquinolin-8(9H)-one. The cyclization products were converted into 8-chloro derivatives, and the chlorine atom therein was replaced by various amines.     

Synthesis of pyrrolo[3,2-<Emphasis Type="Italic">d</Emphasis>][1,3]thiazoles

By oxidation of monothiooxamides with K₃[Fe(CN)₆]pyrrolo[3,2-d][1,3]thiazoledicarboxylic acid was obtained used further in the synthesis of 2,4,5-trimethyl-4H-pyrrolo[3,2-d][1,3]thiazole.     

Reactions of 1,3-Dialkyl-5-amino-1,3-dihydro-2<Emphasis Type="Italic">H</Emphasis>-imidazo-[4,5-<Emphasis Type="Italic">b</Emphasis>]pyridin-2-ones with acetylacetone and ethyl acetoacetate

1,3-Dialkyl-5-amino-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-ones reacted with acetylacetone to give the corresponding 4-(1,3-dialkyl-2-oxo-1,3-dihydro-2H-imidazo[4,5-b]pyridin-5-ylamino)pent-3-en-2-ones which underwent intramolecular cyclization to 1,3-dialkyl-5,7-dimethyl-1,3-dihydro-2H-imidazo[4,5-b]-[1,8]naphthyridin-2-ones on heating in polyphosphoric acid or diphenyl ether. Analogous reaction of 1,3-dialkyl-5-amino-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-ones with ethyl acetoacetate led to the formation of ethyl 3-(1,3-dialkyl-2-oxo-1,3-dihydro-2H-imidazo[4,5-b]pyridin-5-ylamino)but-2-enoates whose cyclization afforded 1,3-dialkyl-8-hydroxy-7-methyl-1,3-dihydro-2H-imidazo[5,4-b][1,8]naphthyridin-2-ones.     

Synthesis and properties of 1-aroyl-5,5-dialkyl-2,3,5,6-tetrahydropyrrolo[ 2,1-<Emphasis Type="Italic">a</Emphasis>]isoquinoline-2,3-diones

Acylation of 1-methyl-3,3-dialkyl-3,4-dihydroisoquinolines with acid chlorides afforded enaminoketones. Enaminophenylketones from the obtained series were reacted with oxalyl chloride to provide 1-benzoyl-5,5-dialkyl-2,3,5,6- tetrahydropyrrolo[2,1-a]isoquinoline- 2,3-diones. The reaction of the latter with binucleophiles leads to the opening of the pyrrole ring and to the heterocyclization: Under the effect of o-phenyldiamine qinoxaline is formed, 1,2-cyclohexanediamine provides the hexahydro-benzimidazole system, о-aminophenol gives benzoxazole, 3-hydroxy-2-amino-pyridine furnishes oxazolo[4,5-b]pyridine. In the reaction with hydrazine hydrate the acylation occurs with hydrazide formation.     

Synthesis of 1-(1,3-dialkyl-2-oxo-2,3-dihydro-1<Emphasis Type="Italic">H</Emphasis>-imidazo-[4,5-<Emphasis Type="Italic">b</Emphasis>]pyridin-5-yl)-5-oxopyrrolidine-3-carboxylic acids

Nitration of 2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-one gave its 5-nitro derivative which was subjected to alkylation with dimethyl sulfate, diethyl sulfate, and benzyl(dimethyl)phenylammonium chloride. The resulting 1,3-dimethyl-, 1,3-diethyl-, and 1,3-dibenzyl-5-nitro-2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-ones were reduced to the corresponding 1,3-dialkyl-5-amino-2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-ones, and the latter reacted with itaconic acid to produce 1-(1,3-dialkyl-2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-5-yl)-5-oxopyrrolidine-3-carboxylic acids. 1-(2-Oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-5-yl)-5-oxopyrrolidine-3-carboxylic acid was obtained by analogous reaction with 5-amino-2,3-dihydro-1H-imidazo[4,5-b]-pyridin-2-one.     

Reaction of 2-R-benzo[<Emphasis Type="Italic">d</Emphasis>]-1,3,2-oxazophosphorin-8-one with hexafluoroacetone. Synthesis and steric structure of 3-phenyl-9,9-bis(trifluoromethyl)-2-ethoxybenzo[<Emphasis Type="Italic">d</Emphasis>]-1,3,2-oxazaphosphepine-2,8-dione

Reaction of hexafluoroacetone with 2-R-benzo[d]-1,3,2-oxazophosphorin-8-ones leads to the formation of seven-membered nitrogen-containing heterocycles, the derivatives of 3-phenyl-9,9-bis (trifluoromethyl)benzo[d]-1,3,2-oxaza-phosphepine-2,8-diones. Steric structure of 2,3-diphenyl-9,9-bis (trifluoromethyl)-benzo[d]-1,3,2-oxazaphosphepine-2,8-di-one was established by X-ray structural analysis. By hydrolysis of the phosphepines a functionally substituted fluorinated ketone, 2-hydroxy-1-(2′-phenylamino)phenyl-2-trifluoromethyl-3,3,3-trifluoro)propan-1-one, was obtained.     

Synthesis of 2,3,4-triphenyl-6,8-dihydropyrrolo-[3,2-<Emphasis Type="Italic">d</Emphasis>][1,2]diazepin-7(1<Emphasis Type="Italic">H</Emphasis>)-one—A novel heterocyclic system

The first representative of a new heterocyclic system, 2,3,4-triphenyl-6,8-dihydropyrrolo[3,2-d]-[1,2]diazepin-7(1H)-one, has been synthesized following an approach based on the reaction of ethyl (3-benzoyl-4,5-diphenyl-1H-pyrrol-2-yl)acetate with hydrazine hydrate.     

Recyclization of 1,3-dialkyl-6-nitro-1<Emphasis Type="Italic">H</Emphasis>-imidazo[4,5-<Emphasis Type="Italic">b</Emphasis>]pyridine-2,5(3<Emphasis Type="Italic">H</Emphasis>,4<Emphasis Type="Italic">H</Emphasis>)-diones into imidazole derivatives

Treatment of 5-amino-1,3-dialkyl-2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-ones with sodium nitrite in aqueous HCl gave 1,3-dialkyl-1H-imidazo[4,5-b]pyridine-2,5(3H,4H)-diones which were nitrated with potassium nitrate in sulfuric acid to 6-nitro derivatives, and the latter underwent recyclization into 4-amino-1,3-dialkyl-5-(1H-pyrazol-5-yl)-2,3-dihydro-1H-imidazol-2-ones by the action of hydrazine hydrate.     

Thienooxazolopyrimidinium salts. Reaction of 1-bromomethyl-5-oxo-4-phenyl-1,2,4,5,6,7,8,9-octahydro[1]benzothieno-[3,2-<Emphasis Type="Italic">e</Emphasis>][1,3]oxazolo[3,2-<Emphasis Type="Italic">a</Emphasis>]pyrimidin-11-ium bromide with oxygen-centered nucleophiles

Reactions of [1]benzothieno[3,2-e][1,3]oxazolo[3,2-a]pyrimidin-11-ium bromide with oxygen-containing nucleophiles involve opening of the dihydrooxazole ring and lead to the formation of new functionally substituted thieno[2,3]-d]pyrimidine derivatives.     

The synthesis of substituted 5-aminopyrido[3′,2′:4,5]thieno[3,2-<Emphasis Type="Italic">c</Emphasis>]isoquinolines and their sulfinyl and sulfonyl derivatives

5-Aminopyrido[3′,2′:4,5]thieno[3,2-c]isoquinolines were synthesized via alkylation of 3-cyanopyridine-2(1H)-thiones with 2-(chloromethyl)benzonitrile followed by treatment of the products with potassium tert-butoxide. The oxidation of the alkylated products to corresponding sulfoxides or sulfones followed by treatment with potassium tert-butoxide provided the corresponding 11-oxides or 11,11-dioxides.     

Hetero-Diels–Alder Reaction of Aroylpyrrolo[1,2-<Emphasis Type="Italic">a</Emphasis>]quinoxalinetriones with Styrene

Hetero-Diels–Alder reaction of 3-aroylpyrrolo[1,2-a]quinoxaline-1,2,4(5H)-triones with styrene afforded diastereoisomeric (5R*,6aR*)- and (5S*,6aR*)-3,5-diaryl-5,6-dihydropyrano[4′,3′:2,3]pyrrolo[1,2-a]-quinoxaline-1,2,7(8H)-triones.     

Diastereoselective 1,3-Dipolar Cycloaddition of Nitrones to 1<Emphasis Type="Italic">H</Emphasis>-Pyrrole-2,3-diones. Synthesis of pyrrolo[3,2-<Emphasis Type="Italic">d</Emphasis>]isoxazoles

1H-pyrrol-2,3-diones react with nitrones affording substituted pyrrolо[3,2-d]isoxazoles. The structures of ethyl (3R*,3aR*,6aR*)-6-benzyl-3-(4-bromophenyl)-4,5-dioxo-2,6a-diphenylhexahydro-3aHpyrrolo[ 3,2-d]isoxazole-3a-carboxylate and dimethyl (3R*,3aR*,6aS*)-3-(4-bromophenyl)-4,5-dioxo-2,6-diphenyltetrahydro-3aH-pyrrolo[3,2-d]isoxazole-3a,6a(4H)-dicarboxylate were proved by single-crystal X-ray analysis.     

Hetero-diels–alder reaction of 5-ylidene-4-sulfanylidene-1,3-thiazolidin-2-ones with <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′-bis(methoxycarbonyl)-1,4-benzoquinone diimine

Hetero-Diels–Alder reaction of 5-(propan-2-ylidene)-4-sulfanylidene-1,3-thiazolidin-2-one with N,N′-bis(methoxycarbonyl)-1,4-benzoquinone diimine in boiling toluene afforded 87% of dimethyl 9,9-dimethyl-2-oxo-8a,9-dihydro-2H-thiochromeno[2,3-d][1,3]thiazole-5,8(3H,4aH)-diylidenedicarbamate. Analogous reactions of 5-benzylidene-, 5-{[4-(dimethylamino)phenyl]methylidene}-, and 5-[(2-hydroxyphenyl)-methylidene]-4-sulfanylidene-1,3-thiazolidin-2-ones led to the formation of the corresponding dimethyl 9-aryl-2-oxo-3,9-dihydro-2H-thiochromeno[2,3-d][1,3]thiazole-5,8-diyldicarbamates in 64–82% yield.     

New Quinoxaline-Containing Monomers for Narrow-Bandgap Polymers

Two new fused quinoxaline-containing monomers—2,3-bis(9-(2-decyltetradecyl)-9H-carbazol-3-yl)dithieno[3,2-f:2'3'-h]quinoxaline (М1) and 2,5-di(nonadecan-3-yl)bis[1,3]thiazolo[4,5-a:5',4'-c]bisthieno[3,2-h:2',3'-j]phenazine (М2)—have been synthesized in high yields of 88 and 83% as promising building blocks of D-A polymers for photovoltaic applications. The optical bandgaps, found from the absorption edge, are 2.79 and 2.88 eV, respectively. The HOMO/LUMO energies of М1 and М2 are–5.83/–2.96 and–5.83/–2.98 eV, respectively. Both monomers have low-lying HOMO levels, which is favorable for a high open-circuit voltage and a high stability in air in the development of PSCs. The E _g ^ec values of monomers М1 and М2 are 2.87 and 2.85 eV and are consistent well with the optical bandgap (2.79 and 2.88 eV, respectively).     

Reactions of 3-Aroylpyrrolo[1,2-<Emphasis Type="Italic">a</Emphasis>]quinoxaline-1,2,4(5<Emphasis Type="Italic">H</Emphasis>)-triones with 2,3-Dihydrofuran and 3,4-Dihydro-2<Emphasis Type="Italic">H</Emphasis>-pyran

3-Aroylpyrrolo[1,2-a]quinoxaline-1,2,4(5H)-triones reacted with 2,3-dihydrofuran and 3,4-dihydro-2H-pyran to give mixtures of the corresponding hetero-Diels–Alder (furo- and pyrano[3″,2″: 5′,6′]pyrano- [4′,3′: 2,3]pyrrolo[1,2-a]quinoxalines) and Michael adducts (furyl- and pyranylpyrrolo[1,2-a]quinoxalines).