Reactivity of N-arylsulfonyl-1,4-benzoquinone imines. Reaction with hydrazoic acid

N-Arylsulfonyl-2-halo-1,4-benzoquinone imines react with hydrazoic acid in boiling acetic acid via two pathways: the 1,4-addition and nucleophilic replacement of the halogen atom by an azido group, followed by the 1,4-addition of HN₃. In the reaction of N-arylsulfonyl-2,6-dihalo-1,4-benzoquinone imines with hydrazoic acid, both halogen atoms are replaced by azido groups, while N-p-tolylsulfonyl-2-methyl-1,4-benzoquinone imine takes up HN₃ molecule according to the 1,4-addition pattern.     

Reaction of 2-(4-alkylpiperazino)-3-chloro-1,4-naphthoquinones with sodium azide

It was shown that 2-(4-alkylpiperazino)-3-chloro-1,4-naphthoquinones react on heating with NaN₃ in DMF to form new heterocyclic quinones — 1,2,3,4-tetrahydro-13-alkyl-3,1-(iminoethano)benzo[g]quinoxaline-5,10-diones as well as the corresponding 2-(4-alkylpiperazino)-3-aminonaphthoquinones and naphthimidazopyrazinediones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2103–2107, September, 1990.     

Hydrochlorination and Hydrobromination of N-(N-Arylsulfonylbenzimidoyl)-1,4-benzoquinonimines

The direction of hydrohalogenation of N-substituted p-quinonimines was predicted on the basis of orbital coefficients of the C² and C³ atoms in the lowest unoccupied molecular orbital, calculated by the PM3 method. It was assumed that the reaction is orbital-controlled and that the initial act of hydrohalogenation is nucleophilic attack by halide ion. The proposed approach was verified by experimental hydrochlorination and hydrobromination of N-(N-arylsulfonylbenzimidoyl)-1,4-benzoquinonimines which take up HHlg molecule following the 1,4-addition scheme, i.e., the halogen atom adds to C² of the quinoid ring.     

Synthesis, X-Ray Diffraction Data, and 1H and 13C NMR Spectra of N-(N-Arylsulfonylimidoyl)-1,4-benzoquinonimines Derived from N-Aroyl(acetyl)-1,4-benzoquinonimines

Oxidation of N-(N-arylsulfonylimidoyl)-4-aminophenols gave the corresponding N-[N-arylsulfonylimidoyl)-1,4-benzoquinonimines, derivatives of N-aroyl- and N-acetyl-1,4-benzoquinonimines. The structure of the products was studied by the X-ray diffraction method and ¹H and ¹³C NMR spectroscopy. N-(N-Arylsulfonylimidoyl)-1,4-benzoquinonimines were found to undergo fast (on the NMR time scale) Z E isomerization about the CÍN bond in the quinonimine fragment. N-(N-Arylsulfonylacetimidoyl)-1,4-benzoquinonimines in solution give rise to dynamic Z E-isomerization with respect to the CÍN bond in the N-arylsulfonylacetimidoyl fragment.     

Palladium-catalyzed desulfitative arylation of sulfonamides with sodium arylsulfinates

A Pd(II)-catalyzed desulfitative arylation protocol between sulfonamides and sodium arylsulfinates was herein reported. The direct arylation reaction was successfully achieved by a Pd(II)/Ag(I)-mediated system without participation of any external ligands with a release of SO₂. And different N-aryl sulfonamides were obtained readily in up to 86% yields, exhibiting good functional groups tolerance (25 examples).     

Reaction of N-phenyl(benzylidene,phenoxy)acetyl-1,4-benzoquinone imines with sodium azide

N-Phenyl(benzylidene, phenoxy)acetyl-1,4-benzoquinone imines reacted with sodium azide to give the corresponding 1,4-addition products, N-(4-hydroxyphenyl) carboxamides. Quantum chemical calculations showed that the initial step in the examined reaction is addition of azide ion to neutral quinone imine molecule.     

Reaction of N-arylcarbamoyl-1,4-benzoquinone imines with sodium azide

N-Arylcarbamoyl-1,4-benzoquinone imines reacted with sodium azide in completely regioselective fashion according to the 1,4-addition pattern with formation of 1-(3-azido-4-hydroxyphenyl)-3-arylureas. The reaction of N-arylcarbamoyl-2,6-dichloro-3,5-dimethyl-1,4-benzoquinone imines with sodium azide afforded N-arylcarbamoyl-2,6-diazido-3,5-dimethyl-1,4-benzoquinone imines as a result of nucleophilic substitution of the chlorine atoms.     

Reaction of sodium bis(trimethylsilyl)amide with 2-bromopyridine

A reaction of sodium bis(trimethylsilyl)amide with 2-bromopyridine leads to N,N-bis(trimethylsilyl)- and N,3-bis(trimethylsilyl)-2-pyridinamine.     

3-硫代甲酰基中氮茚(硫醛)与碘化1,2-及1,4-二甲基吡啶鎓盐的反应

用改进的Vilsmeier反应由3位未取代的中氮茚合成了一系列3-硫代甲酰基中氮茚(硫醛),对其在甲醇溶液中哌啶催化下与碘化1,2-二甲基吡啶鎓盐及碘化1,4-二甲基吡啶鎓盐的缩合反应进行研究,高收率地合成了相应含中氮茚环的二甲川菁,产物结构经元素分析、红外光谱、¹H谱及质谱确证,并测定了其在固态下的荧光性质.结果表明,所有的化合物发射波长都在400nm以上,有希望成为发光材料.     

Reaction of N-arylcarbamoyl-1,4-benzoquinone imines with sodium arenesulfinates

N-Arylcarbamoyl-1,4-benzoquinone imines possessing at least one free ortho position with respect to the carbonyl carbon atom in the quinoid ring react with sodium arenesulfinates according to the nucleophilic 1,4-addition pattern with complete regioselectivity. If both ortho positions are occupied, the reaction gives a mixture of products where the major ones are 1,6- and 6,1-adducts formed according to the radical ion mechanism.     

Synthesis of N-arylsulfonyl-2-aryl(hetaryl)aminoacetic acids

Hydrolytic transformations of 4-[2,2,2-trichloro-1-(arylsulfonylamino)-and-(ethoxycarbonylamino)ethyl]phenyloxy(or sulfanyl)acetic acids under microwave irradiation in alkaline medium involve both trichloromethyl group and ester fragment to give N-arylsulfonyl-2-[4-carboxymethyloxy(or sulfanyl)phenyl]-2-aminoacetic acids in good yields. Hydrolysis of methyl 4-[2,2,2-trichloro-1-(arylsulfonylamino)ethyl]phenyloxy(or sulfanyl)acetates without microwave activation occurs only at the ester group with quantitative formation of 4-[2,2,2-trichloro-1-(arylsulfonylamino)ethyl]phenyloxy(or sulfanyl) acetic acids. N-[2,2,2-Trichloro-1-(1-naphthyl, 2-furyl, and 1-methylindol-3-yl)ethyl]-4-chlorobenzenesulfonamides in alkaline medium under microwave irradiation were converted in 10–15 min into the corresponding N-(4-chlorophenylsulfonyl)-2-aryl-2-aminoacetic acids in preparative yields.     

Halogenation of N-substituted p-quinone imines and p-quinone oxime esters: IV. Chlorination and bromination of N-arylsulfonyl-2(3)-methyl(2-chloro)-1,4-benzoquinone monoimines

The addition of halogens to N-arylsulfonyl-1,4-benzoquinone imines, which exist in a solution as Z and E isomers, is controlled by the steric factor. Z-E Isomerization strongly affects the stability of cyclohexene structures formed by halogenation of 1,4-benzoquinone imines. The halogenation of N-arylsulfonyl-1,4-benzoquinone imines was found to be accompanied by prototropic rearrangement.     

Reaction of some N-substituted 1,4-benzoquinone imines with sodium arenesulfinates

N-Arylsulfonyl, N-aroyl, and N-[arylsulfonylimino(phenyl)methyl] derivatives of 1,4-benzoquinone imine reacted with sodium arenesulfinates to give 1,4-, 1,6-, and 6,1-addition products which were formed according to two concurrent paths: direct nucleophilic addition of arenesulfinate anion to neutral quinone imine molecule and radical ion addition of arenesulfinate radical to radical anion derived from quinone imine.     

A highly efficient palladium-catalyzed desulfitative arylation of azoles with sodium arylsulfinates

A highly efficient palladium-catalyzed direct desulfitative arylation of azoles at C2-position has been developed using sodium arylsulfinates as aryl sources. Azoles including benzoxazoles, benzothiazoles, oxazoles, thiazoles, and 1,3,4-oxadiazoles reacted with sodium arylsulfinates smoothly to generate the corresponding products in good to excellent yields, and various substitution patterns were tolerated toward the reaction.     

Reaction of 3(Z)-benzoylmethylidene-6-nitro-3,4-dihydro-2H-1,4-benzooxazin-2-one with oxalyl chloride

3(Z)-Benzoylmethylidene-6-nitro-3,4-dihydro-2H-1,4-benzooxazin-2-one reacts with (COCl)₂ as imino enol rather than enamino ketone. The reaction is accompanied by replacement of the hydroxy group by chlorine. The molecular and crystal structures of the starting 1,4-benzooxazin-2-one and its chlorinated derivative were studied by X-ray diffraction analysis.     

Reaction of 2-mercaptobenzimida(thia)zole with 1,4-naphthoquinone and its oxide

The reaction of 2-mercaptobenzimida(thia)zole with 1,4-naphthoquinone proceeds as nucleophilic 1,4-addition to give the corresponding thioethers. The reaction of 1,4-naphthoquinone oxide with 2-mercaptobenzimidazole leads to benzimidazonaphthothiazole, while the reaction of the oxide with 2-mercaptobenzothiazole leads to a thioether as a consequence of the addition of the mercapto-substituted heterocycle at the oxide ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 121–124, January, 1992.     

The Reaction of Triplet 2-Methyl-1,4-Naphthoquinone (Menadione) with DNA and Polynucleotides

Abstract— The photoreaction of 2-methyl-l,4-naphthoquinone (MQ, menadione) with DNA and polynucleotides in argon-saturated aqueous solution (pH 7) was studied. Results from laser flash photolysis experiments indicate that triplet quinone reacts with DNA and polyA but not detectably with polyU by one-electron oxidation of the bases of the nucleic acid with formation of the radical anion of the quinone. Irradiation of argon-saturated solutions containing MQ and DNA or polynucleotides (polyU, polyA, polyG or polyC) with 334 nm light leads to an increase in molecular weight for single-stranded DNA, polyA and to a much less extent for polyU. This finding indicates crosslink formation with quantum yields in the range of 10⁻⁵-10⁻³     

Studies on the interaction of Eu(III) with lawsone (2-hydroxy-1,4-naphthoquinone), lapachol (2-hydroxy-3-(3-methyl-2-butenyl)-1,4-naphthoquinone), juglone (5-hydroxy-1,4-naphthoquinone) and plumbagin (2-methyl-5-hydroxy-1,4-naphthoquinone)

pH-metric studies show that one mole of Eu(III) interacts with three molecules of each of juglone, plumbagin, lawsone and lapachol in solution. The stability and thermodynamics of these systems (50% aqueous acetone, 0.1 M KNO₃ ionic strength) are discussed and explained.     

Reaction of sodium octahydrotriborate with biscyclopentadienylzirconium(IV) dichloride

Conclusions Sodium octahydrotriborate reacts with Cp₂ZrCl₂ in THF, ether or CH₂Cl₂ to give Cp₂ZrClBH₄.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 417–419, February, 1984.