Syntheses of spiro[indazole-3,3′-indolin]-2′-ones and spiro[indazole-3,3′-indolin]-2′-imines via 1,3-dipolar cycloadditions of arynes and studies on their isomerization reactions

A 1,3-dipolar cycloaddition reaction of arynes with 3-diazoindolin-2-ones under mild conditions in excellent yields has been developed, which allows facile access to a library of labile spiro[indazole-3,3′-indolin]-2′-ones. Spiro[indazole-3,3′-indolin]-2′-imines could be obtained as well following the same protocol. The isomerization reaction of spiro[indazole-3,3′-indolin]-2′-ones under thermal or acidic conditions has been efficiently achieved to afford a wide range of indazolo-[2,3-c]quinazolin-6(5H)-ones and the one-pot synthesis of indazolo-[2,3-c]quinazolin-6(5H)-ones from arynes and 3-diazoindolin-2-ones is also described. Whereas, spiro[indazole-3,3′-indolin]-2′-imines could not undergo the same rearrangement.     

A new rearrangement of spiro[indane-1,3′-thiophene] and spiro[naphthalene-1,3′-thiophene] derivatives accompanied by opening of the cycloalkane ring

Abstract  

The new thioamides 2-oxoindane-1-carbothioamides and 2-oxo-1,2,3,4-tetrahydronaphthalene-1-carbothioamides underwent conjugated addition to (E)-β-nitrostyrenes followed by cyclization to give products containing 5-hydroxyimino-2-aryliminothiophene rings spiro-annulated to the 2-indanone or 2-tetralone system. On treatment with hydrochloric acid in boiling methanol the compounds underwent a new rearrangement, involving transformation of the 2-aryliminothiophene ring to a pyrrole and an opening of the alicyclic ring in the proximity of the carbonyl group, affording 2-(1,3-diaryl-2-oxo-5-thioxopyrrol-4-yl)benzeneacetic or 2-(1,3-diaryl-2-oxo-5-thioxopyrrol-4-yl)benzenepropanoic acid methyl esters. The structures of two selected pyrrole derivatives were determined by X-ray crystal analyses. The thioamides derived from 2-indanone showed unexpected reactivity towards primary alcohols and underwent conversion to 2-hydroxy-1H-indene-3-thiocarboxylic acid O-esters.     

1,3-Dipolar cycloaddition of diazocyclopropane to strained cycloalkenes and conjugated dienes to give spiro(1-pyrazoline-3,1′-cyclopropanes)

Polycyclic spiro(1-pyrazoline-3,1-cyclopropanes) were obtained in 32–70 % yields by the reaction of diazocyclopropane generatedin situ with 2-methyltricyclo[3.2.1.0^2,4]oct-6-ene, spiro[2,4]hepta-4,6-diene dimer, benzvalene, spiro[2,3]hex-1-ene, methyl 1-methylcyclopropene-3-carboxylate, buta-1,3-diene, and 2-methylbuta-1,3-diene.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2199–2202, November, 1995.This study was financially supported by the Russian Foundation for Basic Research (Grant No. 94-03-08902).     

Synthesis of New Spiro[1,4,2-dioxazole-5,3′-indolin]-2′-one by 1,3-Dipolar Cycloaddition

Novel spiro[1,4,2-dioxazole-5,3′-indolin]-2′-one derivatives were synthesized by 1,3-dipolar cycloaddition reactions of the isatin derivative with aryl nitrile oxide. The cycloadducts were characterized by spectral data including ¹H NMR, ¹³C NMR, infrared, mass spectra, and elementary analysis.     

1,3-Dipolar cycloaddition of cyclic α-methoxynitrones, derivatives of 2H-imidazole 1-oxide and 4H-imidazole 3-oxide

The reactions of cyclic aldo- and -methoxynitrones of the 2H-imidazole-1-oxide and 4H-imidazole 3-oxide series with isocyanates, phenyl isothiocyanate, N-phenylmaleimide, and dimethyl acetylenedicarboxylate were studied. The reactions give the corresponding 1,3-dipolar cycloaddition products. 2,2-Dimethyl-4-phenyl-2H-imidazole 1-oxide does not enter into a similar reaction with isocyanates or phenyl isothiocyanate.     

1,3-Dipolar cycloaddition of 3-phenylamino-5-phenylimino-1,2,4-dithiazole to 1-acyl-2-phenylacetylenes—A new route to functionalized 1,3-thiazole derivatives

3-Phenylamino-5-phenylimino-1,2,4-dithiazole reacted with 1-acyl-2-phenylacetylenes in ethanol or toluene on heating (78–80°C, 1 h) in chemo- and regioselective fashion to give previously unknown N-[5-acyl-3,4-diphenyl-1,3-thiazol-2(3H)-ylidene]-N′-phenylthioureas (yield 57–60%). The structure of N-[5-benzoyl-3,4-diphenyl-1,3-thiazol-2(3H)-ylidene]-N′-phenylthiourea was proved by X-ray analysis.     

Synthesis of novel spiro[indole-3,3′-pyrrolidin]-2(1H)-ones

Diastereoselective [3+2] cycloaddition of azomethine ylide to 1,3-dimethyl-6-(2-oxo-1,2-dihydro-3H-indol-3-ylidene)-3a,9a-diphenyl-3,3a,9,9a-tetrahydroimidazo[4,5-e]thiazolo[3,2-b]-[1,2,4]triazine-2,7(1H,6H)-dione yields hitherto unknown 1,1′,3-trimethyl-3a,9a-diphenyl-3,3a,9,9a-tetrahydrodispiro(imidazo[4,5-e]thiazolo[3,2-b][1,2,4]triazine-6,3′-pyrrolidine-4′,3″-indole)-2,2″,7(1H,1″H)-triones.     

Synthesis of spiro[furan-3,3′-indolin]-2′-ones by PET-catalyzed [3+2] reactions of spiro[indoline-3,2′-oxiran]-2-ones with electron-rich olefins

An efficient procedure for the synthesis of spiro[furan-3,3′-indolin]-2-ones and dispiro[cycloalkane-1,2′-furan-3′,3″-indolin]-2″-ones has been achieved in high yields and stereoselectivity by photoinduced electron transfer-catalyzed [3+2] reactions of substituted spiro[indoline-3,2′-oxiran]-2-ones with olefins. The reactions proceed by ring opening of spiro[indoline-3,2′-oxiran]-2-ones via C_β–O bond cleavage and subsequent cycloaddition with olefins by using 2,4,6-triphenylpyrylium tetarfluoroborate (TPT) as a sensitizer.     

A facile regio- and stereoselective synthesis of novel spiro[indolin-3,2′-pyrrolidin]-2-one’s via 1,3-dipolar cycloaddition of azomethine ylides

A facile regio and stereoselective synthesis of novel spiro[indolin-3,2′-pyrrolidin]-2-one’s have been accomplished through 1,3-dipolar cycloaddition of azomethine ylides generated in situ from the reaction of isatin and benzyl amine with quinoline bearing dipolarophiles in good yields. The synthesized compounds were well characterized through different spectroscopic techniques, such as single crystal XRD, FTIR, NMR, and mass spectral analysis.     

A facile regio- and stereoselective synthesis of novel dispirooxindolyl-[acridine-2′,3-pyrrolidine/thiapyrrolizidine]-1′-ones via 1,3-dipolar cycloaddition of azomethine ylides

A facile regio- and stereoselective synthesis of novel dispirooxindolyl-[acridine-2′,3-pyrrolidine]-1′-ones and dispirooxindolyl-[acridine-2′,3-thiapyrrolizidine]-1′-ones have been accomplished via 1,3-dipolar cycloaddition of azomethine ylides, generated in situ from the reaction of sarcosine/1,3-thiazolane-4-carboxylic acid and substituted isatins, to a series of (E)-2-[arylmethylidene]-3,4-dihydro-1(2H)-acridinones in good yields.     

Efficient multicomponent synthesis of spiro[indoline-3,4′-thiopyran]-2-ones

Synthesis of new thiopyran fused spirooxindoles (spiro[indoline-3,4′-thiopyran]-2-ones) were achieved by a multicomponent reaction of N-methyl isatin, malononitrile/ethyl cyanoacetate, and β-oxodithioester using N,N′-dimethylaminopyridine as the catalyst.     

Synthesis of Spiro[pyrrole–pyrrolizidines] by 1,3-Dipolar Cycloaddition of Azomethine Ylides to 3-Ylidenepyrrol-2-ones

Russian Journal of Organic Chemistry - The Knoevenagel condensation of 1H-pyrrole-2,3-diones with malononitrile gave 3-(dicyanomethylidene)-2,3-dihydro-1H-pyrrole-2-ones which were brought into...     

Synthesis of 4′-alkyl-8-azaspiro[bicyclo[3.2.1]octane-3,2′-morpholin]-5′-ones

N-Boc-protected 8-azaspiro[bicyclo[3.2.1]octane-3,2′-oxirane] reacted with primary aliphatic amines through opening of the epoxide ring with formation of the corresponding amino alcohols which were converted into N-chloroacetyl derivatives. The latter underwent cyclization to N-Boc-protected 4′-alkyl-8-azaspiro[bicyclo[3.2.1]octane-3,2′-morpholin]-5′-ones by the action of sodium hydride in DMF, and subsequent treatment with hydrogen chloride in ethyl acetate afforded 8-azaspiro[bicyclo[3.2.1]octane-3,2′-morpholin]-5′-one hydrochlorides.     

Catalyst and solvent-free cyclopropanation of electron-deficient olefins with cyclic diazoamides for the synthesis of spiro[cyclopropane-1,3′-indolin]-2′-one derivatives

A novel series of spirooxindolylcyclopropane derivatives have been synthesized in high yields from 3-diazooxindole and electron deficient olefins under catalyst/solvent-free conditions.     

Synthesis of new heterocyclic systems—substituted spiro[chromene-4,3′-indoles] and spiro[indole-3,4′-quinolines]

Methods have been developed for the synthesis of new heterocyclic systems, spiro[chromene-4,3′- indoles] and spiro[indole-3,4′-quinolines] by the base-catalyzed domino reaction of isatins with 5,5-dimethylcyclohexane- 1,3-dione (or 5,5-dimethyl-3-anilinocyclohex-2-en-1-one) and ethyl cyanoacetate.     

Regioselective [3+2] cycloaddition of nitrile oxides to 1Н-pyrrole-2,3-diones: synthesis of spiro[pyrroledioxazoles]

Chemistry of Heterocyclic Compounds - 1,3-Dipolar cycloaddition of 1H-pyrrole-2,3-diones to nitrile oxides generated in situ from N-hydroxybenzimidoyl chlorides by the action of triethylamine...     

Catalyst-free glycerol-mediated green synthesis of 5′-thioxospiro[indoline-3,3′-[1,2,4]triazolidin]-2-ones/spiro[indoline-3,3′-[1,2,4]triazolidine]-2,5′-diones

The development of new catalyst-free green and efficient protocol to access 5′-thioxospiro[indoline-3,3′-[1,2,4]triazolidin]-2-ones/spiro[indoline-3,3′-[1,2,4]triazolidine]-2,5′-diones, potential privileged scaffolds for drug discovery, is disclosed. Key feature of this methodology is the dual use of glycerol—a recyclable, bioorganic compound, as a solvent cum promoter. Other highlights include use of inexpensive reagents, mild reaction conditions, operational simplicity, short reaction time, no need for chromatographic purification, and high yields.     

Comparison of the electronic absorption spectra of the isomeric 1,1′- and 2,2′-binaphthyl spiro [cyclophosphazene] derivatives

It has been found that the u.v.-spectrum of the monospiro [(2,2′-dioxybinaphthyl-1,1′) cyclophosphazene] (3) closely resembles those of the other previously described 7-membered 2,2′-bridged 1,1′-binaphthyl derivatives. An hitherto unreported effect of the associated influence of α-substitution, β-coupling and the next cyclization on the u.v. absorption of naphthalene chromophore has been shown by the comparison of the electronic spectra of 1-naphthol (5), 1,1′-dihydroxybinaphthyl-2,2′ (6) and monospiro [(1,1′-dioxybinaphthyl-2,2′) cyclophosphazene] (7). Exclusively strong resonance interaction between the conjugated naphthalene rings was evidenced for 7.