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.     

Synthesis of 2-substituted 6,8-dinitro[1,2,4]triazolo[1,5-a]pyridines and the formation of the related zwitterionic σ-adducts

A method for the synthesis of 2-substituted 6,8-dinitro[1,2,4]triazolo[1,5-a]pyridines is proposed. The method includes the reaction of 2-chloro-3,5-dinitropyridine with the corresponding 5-substituted tetrazoles. The resulting compounds react with anhydro bases of α- and γ-methylazinium salts to give zwitterionic σ-adducts. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1405–1407, July, 1999.     

First example of [6π+2π] cycloaddition of 1,2-dienes to 1,3,5,7-cyclooctatetraene catalyzed by CoI compounds

A stereoselective [6π+2π] cycloaddition of 1,2-dienes to 1,3,5,7-cyclooctatetraene in the presence of a multi-component catalytic system CoI₂/dppe/Zn/ZnI₂, which led to the formation of substituted (E)-bicyclo[4.2.2]deca-2,4,7-trienes in 76—87% yields, was accomplished for the first time.     

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.     

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.     

Synthesis of 11-bromo-9-methyl-6-methylene-3-methylthio-5,6,9,10-tetrahydro-8H-[1,2,4]triazolo[3′,4′;3,4]pyrazino[1,2-c]pyrimidine-8,10-dione from 4-allyl-1-(3-methyl-2,4-dioxo-1,2,3,4-tetrahydro-6-pyrimidinylcarbonyl)thiosemicarbazide

4-Allyl-1-(3-methyl-2,4-dioxo-1,2,3,4-tetrahydro-6-pyrimidinylcarbonyl)thiosemicarbazide is cyclized in alkaline medium into 4-allyl-3-(3-methyl-2,4-dioxo-1,2,3,4-tetrahydro-6-pyrimidinyl)-1,2,4-triazoline-3-thione, which is converted on alkylation with iodomethane into the methylthio derivative. Reaction of the latter with bromine occurs with formation of 3-(5-bromo-3-methyl-2,4-dioxo-1,2,3,4-tetrahydro-6-pyrimidinyl)-4-(2,3-dibromopropyl)-5-methylthio-1,2,4-triazole, dehydrobromination of which with potassium carbonate leads to formation of the first representative of a new heterocyclic system, viz. 11-bromo-9-methyl-6-methylene-3-methylthio-5,6,9,10-tetrahydro-8H-[1,2,4]triazolo[3,4:3,4]pyrazino[1,2-c]pyrimidine-8,10-dione.Vilnius University, Vilnius 2734, Lithuania. e-mail: sigitas.tumkevicius@chf.vu.lt. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 67–70, January, 1999.     

Spirocyclohexadienones: XIII. Reactions of schiff bases with enamines derived from 3,4-dihydroisoquinoline and with spiro[naphthalene-1,3′-pyrrol]-4-one

Addition of 1,3,3-trimethyl-3,4-dihydroisoquinolines to N-benzylideneanilines gives substituted N-[2-(3,3-dimethyl-3,4-dihydroisoquinolin-1-yl)-1-phenylethyl]anilines, whereas 2′,5′,5′-trimethyl-4′,5′-dihydro-4H-spiro[naphthalene-1,3′-pyrrol]-4-one reacts with N-benzylideneanilines along two pathways involving cyclization to substituted 2,3,3a,4,10,11-hexahydrobenzo[f]pyrrolo[2,3-d]quinolin-5(1H)-ones or elimination of the aniline residue with formation of substituted 5′,5′-trimethyl-2-styryl-4′,5′-dihydro-4H-spiro[naphthalene-1,3′-pyrrol]-4-ones.     

Investigation of regioselectivity in the synthesis of spiro [pyrrolidine-2,3′-oxindoles] by use of the Huisgen reaction

The Huisgen reaction has been used to synthesize five-membered heterocyclic compounds in high yield and with high regio and stereoselectivity. In the synthesis of spiro [pyrrolidine-2,3′-oxindole] derivatives from isatin, α-amino acids, and (E)-β-phenyl nitroolefins, two regioisomers were obtained in each reaction. The regioselectivity of the major product was found to be different from that in reported work, and was investigated at the B3LYP/6-311G* level of theory. On the basis of this new finding, several conditions, for example molar ratio, solvent, and temperature, which affect the regioselectivity of this reaction were investigated; the results obtained are discussed. It was found that the regioselectivity of this reaction was affected by solvent and temperature, irrespective of the ratio of the reactants. Low temperature and high solvent polarity leads to high regioselectivity, and protic solvents result in higher yield and regioselectivity. These results are of benefit for regioselective synthesis of some compounds.     

Synthesis and Bioactivity of Some New 2-(Alkoxy carbonyl alkyl)-6-bromo-3,4-dihydro-3-(α-methyl benzyl)-2-oxo- benzo[e] [2H-1,3,2-oxazaphosphinine] Derivatives

Synthesis of some new 2-(alkoxy carbonyl alkyl)-6-bromo-3,4-dihydro-3-(α-methyl benzyl)-2-oxo-3-benzo- [e][2H-1,3,2-oxazaphosphinine] derivatives was accomplished through a two step process, which involves the condensation of 2-[(α-methylbenzyl amino)methyl]-4-bromophenol (1) with phosphorus oxychloride in equimolar quantities in the presence of triethylamine in dry toluene in 50—55 ℃ producing the corresponding intermediate (2), and subsequent reaction with the amino acid alkyl ester in dry tetrahydrofuran in the presence of triethylamine at different temperatures. They exhibited significant antibacterial and fungal activity.     

Cyclopenta[b]thienyl ligand in organometallic chemistry. Studies of the regioselectivity of the synthesis of new σ-element-substituted cyclopenta[b]thiophene derivatives

Reactions of 2-ethyl-5-methylcyclopenta[b]thienyllithium (thiopentalenyllithium) (2) with various electrophilic reagents afford σ-element-substituted thiopentalenes. However, the reaction with Ph₃SnCl yields only one of two possible isomers,viz, triphenyl(4H-cyclopenta[b] thiophen-4-yl)stannane (4c), whereas the reactions with Me₃SiCl, Me₃SiCl, or Ph₂PCl give both possible isomers,viz., trimethyl(6H-cyclopenta[b]thiophen-6-yl)silane (3a) and trimethyl(4H-cyclopental[b]thiophen-4-yl)silane (4a), trimethyl(6H-cyclopenta[b]thiophen-6-yl)stannane (3b) and trimethyl(4H-cyclopental[b]thiophen-4-yl)stannane (4b), or diphenyl(6H-cyclopenta[b]thiophen-6-yl)phosphine (3d) and diphenyl(4H-cyclopenta[b]thiophen-4-yl)phosphine (4d) in ratios of 1∶2, 1∶2, or 1∶1, respectively. The structure of compound4c was established by X-ray diffraction analysis. The observed regioselectivity of formation of compound4c is attributed to the specific precoordination of the tin atom by the sulfur atom of the thiopentalenyl ligand and to the steric overcrowding of the Sn atom in organotin electrophiles. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1285–1289, July, 2000.     

Solvation-induced σ-complex structure formation in the gas phase: a revisit to the infrared spectroscopy of [C6H6-(CH3OH)2]+

Structures of the [C(6)H(6)-(CH(3)OH)(2)](+) cluster cation are investigated with infrared (IR) spectroscopy. While the noncovalent type structure has been confirmed for the n = 1 cluster of [C(6)H(6)-(CH(3)OH)(n)](+), only contradictory interpretations have been given for the spectra of n = 2, in which significant changes have been observed with the Ar tagging. In the present study, we revisit IR spectroscopy of the n = 2 cluster from the viewpoint of the σ-complex structure, which includes a covalent bond formation between the benzene and methanol moieties. The observed spectral range is extended to the lower-frequency region, and the spectrum is measured with and without Ar and N(2) tagging. A strongly hydrogen-bonded OH stretch band, which is characteristic to the σ-complex structure, is newly found with the tagging. The remarkable spectral changes with the tagging are interpreted by the competition between the σ-complex and noncovalent complex structures in the [C(6)H(6)-(CH(3)OH)(2)](+) system. This result shows that the microsolvation only with one methanol molecule can induce the σ-complex structure formation.     

One-pot synthesis of 6H-pyrrolo[2,3-e[1,2,4]triazolo[1,5-a]pyrimidines on the basis of σH-adducts of 6-Nitro[1,2,4]triazolo[1,5-a]pyrimidine with carbonyl compounds

Aromatic, heteroaromatic, and aliphatic carbonyl compounds reacted with 6-nitro[1,2,4]triazolo[1,5-a]pyrimidine in the presence of a base to give stable σ^H-adducts at C⁷. Reduction of the nitro group in the latter is accompanied by tandem autoaromatization of the azine ring and intramolecular cyclocondensation with formation of the corresponding 6H-pyrrolo[2,3-e][1,2,4]triazolo[1,5-a]pyrimidines. Original Russian Text ? E.B. Gorbunov, G.L. Rusinov, R.I. Ishmetova, V.N. Charushin, O.N. Chupakhin, 2008, published in Zhurnal Organicheskoi Khimii, 2008, Vol. 44, No. 1, pp. 130–134. Dedicated to Full Member of the Russian Academy of Sciences G.A. Tolstikov on his 75th anniversary     

First example of the cluster ammine complex [Re6Se7Br(NH3)6]3+: synthesis and structure of the [Re6Se7Br(NH3)6][Re6Se7BrBr6]·12H2O salt

The reaction of Cs₃[Re₆Se₇BrBr₆] with aqueous ammonia afforded the octahedral rhenium ammine cluster complex cation [Re₆Se₇Br(NH₃)₆]³⁺. This cation crystallized as the [Re₆Se₇Br(NH₃)₆][Re₆Se₇BrBr₆]·12H₂O compound. The crystal structure of this compound was established. The presence of the NH₃ ligands in the coordination environment about the Re atom was confirmed by thermogravimetry, vibrational spectroscopy, and high-resolution mass spectrometry. The resulting compound is the first example of salts composed of the cluster cation and cluster anion possessing the same {Re₆Se₇Br} cluster core.     

2,2′-Bis(arylamino)-1,1′-biaryls as Building Blocks for the Synthesis of Dibenzo[d,f][1,3]diazepines,Dibenzo[d,f][1,3]diazepinones,and Dibenzo[c,e][1,2,7]thiadiazepine 6-Oxides

The iron-catalyzed oxidative C−C homocoupling of diarylamines affords 2,2′-bis(arylamino)-1,1′-biaryls which represent crucial synthetic building blocks for an access to a range of seven-membered heterocyclic ring systems. Reaction with paraformaldehyde, diphenyl carbonate, and diphenyl sulfite as efficient 1,1-dielectrophiles led to dibenzo[d,f][1,3]diazepines, dibenzo[d,f][1,3]diazepinones, and dibenzo[c,e][1,2,7]thiadiazepine 6-oxides. The synthetic procedures enable short and practical routes to these 1,3-diazepine derivatives under mild reaction conditions and with a high tolerance of various functional groups.     

A novel three-component method for the synthesis of spiro[chromeno [4′,3′:4,5] pyrimido[1,2-b] indazole-7,3′-indoline]-2′,6(9H)-dione

A green, efficient, and rapid procedure for the synthesis of novel spiro[chromeno[4′,3′:4,5] pyrimido[1,2-b]indazole-7,3′-indoline]-2′,6(9 H)-dione derivatives has been developed by one-pot condensation of 4-hydroxy-2H-chromen-2-one, isatin, and 1H-indazole-3-amine, in the presence of acetic acid in EtOH. This method has the advantages of operational simplicity, and high yield of products via a simple experimental and work-up procedure as compared to the conventional methods. The reaction mechanism and substrate scope of this novel reaction is briefly discussed.     

(4+2) Cycloaddition to tricarbonyl[(1-4-η)-2-methoxy-5-methylene-cyclohexa-1,3-diene]iron for the rapid construction of a spiro[5.5]undecane system

Diels-Alder reactions of tricarbonyl[(1-4-η)-2-methoxy-5-methylene-cyclohexa-1,3-diene]iron 1 with 1,2,4,5-tetrazine-3,6-disubstituted derivatives 2a,b,d and 2,3,4,5-tetrabromothiophene-1,1-dioxide 5 are reported. The (4+2) cycloaddition reactions took place exclusively with highly electron deficient dienes to form spiro[5.5]undecane system in good yield. The more electron rich nature of the 1,2,4,5-tetrazine-3,6-disubstituted derivatives 2b did not react. The reaction also took place stereospecifically exo to the Fe(CO)₃ moiety.     

Synthesis and Crystal Structure of Spiro[1-bromo-4-methoxy-5-oxa-6-oxo-bicyclo[3.1.0]hexane-2,2′-（3′- cyclohexanoxy-4′-methoxybutyrolactone]

1INTRODUCTIONThecyclopropane-containingnaturalproductshavereceivedconsiderableattentionassynthetictar-getsastheincorporationofrigidifiedcyclopropylmotifintobioactiveanaloguescanleadtoconfor-mablyconstrainedmolecules[1,.Suchmodifica-2]tionsareexpectedtohavesignificanteffectsonbio-activitieswithconcomitantmedicalimplications.Des-pitethegreatadvancesinthisfield,theefficientsyn-thesisofspiro-cyclopropanecompoundsstillremainsaconsiderablechallenge.Particularnoticeisthede-ficiencyinthepreviousm…     

Reaction of tricarbonyl[(1-4-η)-2-methoxy-5-vinylidene-cyclohexa-1,3-diene]iron derivatives with carbene: (2+1) cycloaddition for the rapid synthesis of spiro[2,5]octane

Tricarbonyl[(1-4-η)-2-methoxy-5-methylene-cyclohexa-1,3-diene]iron (1a) and tricarbonyl[(1-4-η)-2-methoxy-5-isopropylene-cyclohexa-1,3-diene]iron (1b) complexes are unstable 4-vinylidene cyclohexanone equivalents and these react regio- and stereoselectively with carbenes and metallocarbenes to give spiro[2,5]octane ring system. The (2+1) cycloaddition reaction provides a rapid entry into spiro[2,5]octane ring system. In cases where the carbene and metallocarbene contain a good bulky leaving group or an electron-withdrawing group, the cyclopropane ring-opening products are obtained.     

Efficient Catalytic Synthesis of α,ω-Di(spiro[adamantane2,3′-[1,2,4,5,7]tetroxazocan]-7′-yl)alkanes

Russian Journal of Organic Chemistry - An efficient method has been developed for the synthesis of α,ω-di(spiro[adamantane-2,3′[1,2, 4,5,7]tetroxazocan]-7′-yl)alkanes by...