Porphyrazines of symmetric and unsymmetrical structure with fused fragments of 1,4-bis(2-phenoxyethoxy)benzene and 5,6-diphenylpyrazine. Synthesis and spectral characteristics

By alkylation of 3,6-dihydroxyphthalonitrile with 1-bromo-2-phenoxyethane 3,6-bis(2-phenoxyethoxy) phthalonitrile was obtained. A random condensation of the nitrile with 2,3-dicyano-5,6-diphenylpyrazine in 1-butanol in the presence of lithium 1-butanolate porphyrazines were synthesized of symmetric and unsymmetrical structure, and their spectral characteristics were investigated.     

The Light-Induced Oxygenation of the B-Didehydrocorrinoid Vitamin-B12 Derivative ‘Pyrocobester’

The didehydrocorrinoid derivative of vitamin B₁₂, ‘pyrocobester’ 1 (hexamethyl Coα, Cob?-dicyano-7-de (carboxymethyl)-7,8-didehydrocobyrinate), is oxygenated in the presence of visible light and molecular oxygen to give the previously unknown ‘5,6-dioxosecopyrocobester’ 3 (hexamethyl Coα, Cob?-dicyano-5,6-dioxo-7-de(carboxymethyl)-7,8-didehydro-5,6-secocobyrinate) under regioselective cleavage of the macrocycle at the 5,6-position. Efficiency and yield of this reaction involving ‘singlet oxygen’ depend on the solvent used: with CCl₄ a 96% yield of 3 is obtained.     

Photooxygenolytic Degradation of the Vitamin-B12 Derivative Heptamethyl Coα,Coβ-Dicyanocobyrinate. Efficient Preparation of Bicyclic Fragments

The methylene-blue sensitized photooxygenation of heptamethyl Coα,Coβ-dicyanocobyrinate ( 1 , cobester) at ca. ?45° and in (D₃)acetonitrile solution proceeds readily to the stage of selective double cleavage of the corrin macrocycle. It furnishes the bisected heptamethyl Coα,Coβ-dicyano-5,6:14,15-tetraoxo-5,6:14,15-disecocobyrinate ( 3 ) in 91% yield after warming the photooxygenation mixture to room temperature. Complex 3 is also obtained by photooxygenation of the secocorrinoid oxygenation products of 1 , namely of heptamethyl Coα,Coβ-dicyano-5,6-dioxo-5,6-secocobyrinate ( 2a ) and of its isomer heptamethyl Coα,Coβ-dicyano-14,15-dioxo-14,15-secocobyrinate ( 2b ). When the raw photooxygenation product of 1 is kept at low temperature, 3 is not formed in a significant amount; spectral analysis reveals 4 as intermediate that is transformed into 3 quantitatively upon warm-up and storage at r.t. Compound 4 is assigned the structure of heptamethyl Coα,Coβ-dicyano-5,6-epidioxy-5,6-dihydro-14,15-dioxo-14,15-secocobyrinate, based on NMR-spectral data and since 4 is also formed cleanly in the corresponding low-temperature photooxygenation of 2b . Catalytic reduction of the Co(III) complex 3 (H₂, Pt/C) in the presence of EDTA produces a colourless oil, from which the bicyclic fragments 5 (corresponding to rings A and D of 1 ) and 6 (corresponding to rings B and C of 1 ) are obtained in 99 and 91% yield, respectively, after chromatographic separation.     

Synthesis and Properties of Copper(II) Tetra(2-alkyl-4,5-benzimidazolo)- and Tetra(2,2'-Dimethyl-4,5-benzodiazepino)porphyrazines

4,5-Diaminophthalonitrile was reacted with carboxylic acids and acetylacetone to synthesize 2-alkyl-5,6-dicyanobenzimidazoles and 2,2'-dimethyl-5,6-dicyanobenzodiazepine, respectively. The products were converted into copper(II) porphyrazines. An effect of the heterocyclic residue on the physicochemical and spectral properties of the porphyrazines was revealed.     

Synthesis and Spectral Characteristics of Unsymmetrical Porphirazines with Triphrnylmethyl Groups

Condensation of 4-(p-triphenylmethylphenoxy)-1,2-dicyanobenzene with 1,2-di(methylthio)maledinitrile or 2,3-dicyano-5,6-diphenylpyrazine afforded symmetric and unsymmetrical porphirazines. The effect of their structural modification on the spectral characteristics was investigated.     

The Photooxygenation of Heptamethyl Coα, Coβ-Dicyanocobyrinate

Irradiation with visible light of an oxygen-saturated methanolic solution of heptamethyl Coα, Coβ-dicyanocobyrinate and of the sensitizer methylene blue causes the efficient photooxygenation of this vitamin B₁₂ derivative. Use of CD₃OD instead of CH₃OH strongly accelerates the reaction. This solvent H/D-isotope effect is consistent with a mechanism involving ‘singlet oxygen’ and is exploited preparatively. Two photooxygenation products can be isolated from such preparative experiments. One of these, isolated in 47% yield, has NMR.-spectral characteristics identical with those of Inhoffen's heptamethyl Coα,Coβ-dicyano-5,6-dioxo-5,6-secocobyrinate ( 2a ). To the other photoproduct, isolated in 25% yield, the structure of the unknown isomeric heptamethyl Coα, Coβ-dicyano-14,15-dioxo-14, 15-secocobyrinate ( 3a ) is assigned.     

Synthesis of 4-Alkenylated Pyrazolinones by 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ)-Mediated Oxidative Coupling Reaction

1,3-Diarylpropenes firstly serve as efficient alkenylated reagents for the functionalization of pyrazolinones. In the presence of 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), it undergoes oxidative coupling and final dehydrogenation to give the highly substituted E,E-α,β,γ,δ-dienpyrazolinones in moderate to excellent yields.     

Reaction of 5,5-dialkyl-2-halo-6-hydroxy-5,6-dihydro-1H-pyridine-3,4,4-tricarbonitriles with Morpholine

5,5-Dialkyl-2-halo-6-hydroxy-5,6-dihydro-1H-pyridine-3,4,4-tricarbonitriles reacted with morpholine in aprotic solvent to give the corresponding 3,3-dialkyl-4,5-dicyano-6-halo-2-morpholino-1,2,3,4-tetrahydropyridine-4-carboxamides, while analogous reaction in amphiprotic solvent resulted in the formation of 8,8-dialkyl-3-halo-6-oxo-2,7-diazabicyclo[3.2.1]oct-3-ene-4,5-dicarbonitriles.     

Charge-Transfer Complexes between Substituted Pyridine N-Oxides and 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone

Spectrophotometry was used to study charge-transfer complexes between substituted pyridine N-oxides and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone. Vertical ionization potentials of pyridine N-oxides in the gas phase and in solution were calculated by the CNDO/S3' method. The calculated ionization potentials in chloroform nicely correlate with the experimental charge-transfer wavelengths of the complexes.     

Facile meso Functionalization of Porphyrins by Nucleophilic Substitution with Organolithium Reagents

The ruffle of the porphyrin increases with the number of meso substituents. (Octaethylporphyrin)nickel(II ) undergoes nucleophilic substitution reactions upon treatment with alkylating reagents such as butyllithium, hydrolysis with water, and oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone [DDQ; Eq. (a)]. Alkylation can be achieved at all four meso positions, and access is provided to new nonplanar porphyrins and asymmetrically substituted systems.     

Unsymmetrical Pentoxy-Substituted Porphyrazines

The reactions of 3,6-dipentoxyphthalonitrile (A) in the 1-pentanol - magnesium pentylate medium with phthalonitrile, 2,3-di(methylsulfanyl)-2-butenedinitrile, and 2,3-dihydro-1,4-dithiin-5,6-dicarbonitrile (B) were performed. Unsymmetrically substituted porphyrazines A₃B were prepared and studied. The influence of the structure of fragment B on the spectral characteristics of the porphyrazines was examined.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 3, 2005, pp. 504–508.Original Russian Text Copyright © 2005 by Nikolaev, Kudrik, Kulinich, Shaposhnikov.     

Chemical interactions between 2-mercaptobenzazoles and π-acceptors

Summary 2-Mercaptobenzazoles (1a–c) interact with several -acceptors such as tetracyanoethylene (TCNE) 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), 2,3,5,6-tetrachloro-1,4-benzoquinone (CHL) dicyanomethyleneindane-1,3-dione (CNIND), 2,3-dicyano-1,4-naphthoquinone (DCNQ), 9-dicyanomethylene-2,4,7-trinitrofluorene (DTF), and 2,3-dichloro-1,4-naphthoquinone (DCHNQ)via the formation of charge-transfer (CT) complexes to yield various heterocyclic compounds.

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Chemische Wechselwirkungen zwischen 2-Mercaptobenzazolen und -Akzeptoren

Zusammenfassung Die 2-Mercaptobenzazole1a–c reagieren mit verschiedenen -Akzeptoren wie Tetracyanoethylen (TCNE), 2,3-Dichlor-5,6-dicyano-1,4-benzochinon (DDQ), 2,3,5,6-Tetrachlor-1,4-benzochinon (CHL), Dicyanomethylenindan-1,3-dion (CNIND), 2,3-Dicyano-1,4-naphthochinon (DCNQ), 9-Dicyanomethylen-2,4,7-trinitrofluoren (DTF) und 2,3-Dichlor-1,4-naphthochinon (DCHNQ) unter Ausbildung von charge transfer — Komplexen (CT) zu heterocyclischen Verbindungen.

     

A Stereostructural Study of 17-Hydroxylupanine and its Perchlorate

 The bisquinolizidine carbinolamine 17-hydroxylupanine was synthesized de novo from lupanine using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone; its structure was established by NMR techniques. The equatorial position of the hydroxy group as well as the prevailing boat form of ring C were determined. As expected, the carbinolamine converted into the C17=N16 anhydronium perchlorate upon treatment with HClO₄. NMR analysis of the salt revealed a conformational equilibrium within rings A and D, whereas rings B and C remain rigid.     

Synthesis of non-k-region ortho-quinones of polycyclic aromatic hydrocarbons from cyclic ketones

Non-K-region $\text{o}$-quinones of polycyclic aromatic hydrocarbons are prepared in four steps from cyclic ketones via dehydrogenation of tetrahydrodiols with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone.     

Synthesis of 6-Amino-5-R2-7-(6-R1-4-oxo-3,4-dihydro-2-quinazolyl)-5H-pyrrolo[2,3-b]pyrazine-2,3-dicarbonitriles

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.     

一种功能型混配镍配合物的溶剂化显色特性与结构关系

详细报道了新近合成的二氰基二硫纶·邻菲罗啉二酮合镍配合物Ni(mnt) (phen - 5,6-dione) (mnt2 - ∶1,2 -dicyano - 1,2 -ethylenedithiolateormaleonitriledithiolate ;phen - 5,6-dione∶1,10 -phenanthroline - 5,6-dione)的电子吸收光谱 ,着重研究了可见光区中的溶剂化显色吸收带在相关分子轨道能级图中的对应跃迁关系 ,探讨了LL′CT的本质和感光氧化现象。     

A Stereostructural Study of 17-Hydroxylupanine and its Perchlorate

Summary.  The bisquinolizidine carbinolamine 17-hydroxylupanine was synthesized de novo from lupanine using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone; its structure was established by NMR techniques. The equatorial position of the hydroxy group as well as the prevailing boat form of ring C were determined. As expected, the carbinolamine converted into the C17=N16 anhydronium perchlorate upon treatment with HClO₄. NMR analysis of the salt revealed a conformational equilibrium within rings A and D, whereas rings B and C remain rigid. Received March 13, 2000. Accepted March 21, 2000     

超细粉体二硫纶·菲咯啉二酮混配钴(Ⅱ)配合物的荧光特性和光敏性研究

报道了二氰基二硫纶·菲咯啉 5,6 二酮混配钴(Ⅱ)配合物CoLL′(L=mnt2-.mnt2-为1,2 二氰基乙烯 1,2 二硫醇离子.L′=phen 5,6 dione,1,10 菲咯啉 5,6 二酮)的合成和标题配合物的电子吸收光谱、电子发射光谱.研究了CoLL′对CdS的光敏化作用与其电子光谱间的关系.     

Regioselective Synthesis of 1,3,5-Trisubstituted Pyrazoles

Abstract

A new and a simple approach toward synthesis of 1,3,5-trisubstituted pyrazoles from chalcone arylhydrazones via oxidative cyclization has been achieved. 2,3-Dichloro-5,6-dicyano-1,4-benzoquinone was successfully used as an oxidizing agent to give excellent yields of pyrazoles.     

Interaction of 2-aryl-6-hydroxy-5,6-tetra-methyl-enepiperidine-3,3,4,4-tetracarbonitriles and 2-aryl-5,6-tetramethylene-3,3,4-tricyano-2,3,4,5-tetrahydropyridine-4-carboxamides with ammonia

The interaction of 2-aryl-6-hydroxy-5,6-tetramethylenepiperidine-3,3,4,4-tetracarbonitriles and 2-aryl-5,6-tetramethylene-3,3,4-tricyano-2,3,4,5-tetrahydropyridine-4-carboxamides with ammonia results in the formation of 5-aryl-1,7-tetramethylene-3-imino-4,8-dicyano-2,6-diazabicyclo[2.2.2]octane-8-carboxamides. In solvents, these latter compounds are converted to 3-amino-6-oxo-1,8-tetramethylene-2,7-diazabicyclo-[3.2.1]octa-3-ene-4,5-dicarbonitrile and 2-amino-3-cyano-5,6-tetramethylenepyridine-4-carboxamide. I. N. Ul'yanov Chubash State University, Cheboksary 428015. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 533–541, April, 1997.