4-Functionally Substituted 3-Heterylpyrazoles: IV. Benzylamino[3-aryl(heteryl)-4-pyrazolyl]methylphosphonic Acids

Derivatives of N-benzyl[3-aryl(heteryl)-4-pyrazolyl]methanimines react with diethyl phosphite to afford diethyl benzylamino[3-aryl(heteryl)-4-pyrazolyl]-4-methylphosphonates that on hydrolysis with 18% hydrochloric acid yield the corresponding aminophosphonic acids.     

4-Functionally Substituted 3-Heterylpyrazoles: IV. 1-Phenyl-3-aryl(heteryl)-5-(4-pyrazolyl)-2-pyrazolines

3-Aryl(heteryl)-4-formylpyrazoles in condensation with methyl aryl(heteryl) ketones afforded 1-aryl(heteryl)-3-[3-aryl(heteryl)-4-pyrazolyl]propenones. The latter reacted with phenylhydrazine yielding 1-phenyl-3-aryl(heteryl)-5-(4-pyrazolyl)-2-pyrazolines.     

4-Functionally Substituted 3-Heterylpyrazoles: VIII. 3-Aryl(heteryl)-4-hydroxyl(chloro)methylpyrazoles

3-Aryl(heteryl)pyrazole-4-carbaldehydes were reduced with sodium tetrahydridoborate under mild conditions to give 3-aryl(heteryl)-4-hydroxymethylpyrazoles which were converted into the corresponding 4-chloromethyl derivatives by treatment with thionyl chloride. The subsequent reaction with triphenylphos- phine led to formation of triphenyl(4-pyrazolylmethyl)phosphonium chlorides, and Wittig reaction of the latter with aromatic or heteroaromatic aldehydes yielded 4-[2-aryl(heteryl)ethenyl]pyrazoles.     

4-Functionally-substituted 3-Heterylpyrazoles: XV. 3-Aryl(heteryl)-1-phenyl-4-pyrazolylmethylamines and Heterocumulenes Obtained Therefrom

By reduction of 3-aryl(heteryl)-1-phenyl-4-azidomethyl-pyrazoles in the presence of Raney nickel or by hydrazinolysis of N-[3-aryl(heteryl)-1-phenyl-4-pyrazolylmethyl]phthalimides 4-pyrazolylmethylamines were obtained that in reaction with bis(trichloromethyl) carbonate afforded 3-aryl-(heteryl)-1-phenyl-4-pyrazolylmethyl isocyanates, and with carbon disulfide furnished 3-aryl-(heteryl)-1-phenyl-4-pyrazolylmethyl isothiocyanates.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 2, 2005, pp. 247–251.Original Russian Text Copyright © 2005 by Bratenko, Panimarchuk, Mel’nichenko, Vovk.     

Functionally Substituted 3-Heterylpyrazoles: IX. 3-Aryl(heteryl)-4-mercapto(thiocyanato,isothiocyanato)methylpyrazoles

By reaction of 3-aryl(heteryl)-4-chloromethylpyrazoles with thiourea and sodium thiocyanate respectively 3-aryl(heteryl)-4-mercaptomethylpyrazoles and 3-aryl(heteryl)-thiocyanatomethylpyrazoles were obtained. The latter were subjected to thermal isomerization into 3-aryl(heteryl)-isothiocyanatomethylpyrazoles.     

4-Functionally Substituted 3-Heterylpyrazoles: III. 3-Aryl(heteryl)pyrazole-4-carboxylic Acids and Their Derivatives

3-Aryl(heteryl)-4-formylpyrazoles were cleanly oxidized by potassium permanganate in water-pyridine medium to afford in high yield 3-aryl(heteryl)pyrazole-4-carboxylic acids, that were further converted into the corresponding chlorides and amides.     

Transformation of 4-aryl(heteryl)-2,6-diamino-3,5-dicyano-4H-thiopyrans into substituted acrylonitriles, 1,4-dihydropyridines, 2,3,4,7-tetrahydrothiazolo[3,2-a]pyridine, and 4,7-dihydrothieno[2,3-b]pyridine

Cross-recyclization of 4-aryl(heteryl)-2,6-diamino-3,5-dicyano-4H-thiopyrans with α-bromoketones or alkyl halides formed substituted 3-aryl-2-(4-R-thiazol-2-yl)acrylonitriles, 2-alkylsulfanyl-1,4-dihydropyridines, 2,3,4,7-tetrahydrothiazolo[3,2-a]pyridine, and 4,7-dihydrothieno[2,3-b]pyridine.     

Synthesis of aryl- and heteryl-containing gem-acylnitrocyclohexenes

Reactions of 2-aryl(heteryl)-1-acetyl(benzoyl)-1-nitroethenes with 2,3-dimethyl-1,3-butadiene led to the formation of products of [4+2]-cycloaddition, 1-acyl-6-aryl(heteryl)-3,4-dimethyl-1-nitro-3-cyclohexenes. Their structure was proved by IR and ¹H NMR spectroscopy.     

Synthesis of 1H-pyrazolo[3,4-c]isoquinolin-1-ones by the condensation of cyclohexanone derivatives with 3-amino-1-phenyl-1H-pyrazol-5(4H)-one

The synthesis of 1H-pyrazolo[3,4-c]isoquinolin-1-ones was carried out by reacting 3-aryl(heteryl)-2,4-diacetyl-5-hydroxy-5-methylcyclohexanones with 3-amino-1-phenyl-1H-pyrazol-5(4H)-one. The structure of the 7-acetyl-2,4,6,7,8,9-hexahydro-8-hydroxy-5,8-dimethyl-2-phenyl-6-(fur-2-yl)-1H-pyrazolo[3,4-c]isoquinolin-1-one obtained was proved by X-ray diffraction analysis.     

4-Functionally Substituted 3-Heterylpyrazoles: XIV. <Emphasis Type="Italic">N</Emphasis>-Benzyl-<Emphasis Type="Italic">N</Emphasis>-[3-aryl(heteryl)-4-pyrazolylmethylene]amines and Their Derivatives

Reduction with sodium tetrahydridoborate of Schiff bases derived from 3-aryl(heteryl)pyrazole-4-carbaldehydes and benzylamines gave N-benzyl-N-[3-aryl(heteryl)-4-pyrazolylmethylene]amines which were acylated with benzoyl chloride and succinic and maleic anhydrides to obtain the corresponding amides. Treatment of the title compounds with phenyl isothiocyanate afforded substituted thioureas.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 1, 2005, pp. 98–103.Original Russian Text Copyright © 2005 by Bratenko, Panimarchuk, Chornous, Vovk.     

Chemistry of iminofurans: IX. Synthesis and cyclization of (2<Emphasis Type="Italic">Z</Emphasis>)-2-{(2<Emphasis Type="Italic">Z</Emphasis>)-2-[2-(3-R-adamantan-1-yl)-2-oxoethylidene]hydrazinyl}-4-(het)aryl-4-oxobut-2-enoic acids

1-(3-R-adamantan-1-yl)-2-[(triphenyl-λ⁵-phosphanylidene)hydrazinylidene]ethanone reacted with 4-aryl(hetaryl)-2,4-dioxobutanoic acids to give 2-{2-[2-(3-R-adamantan-1-yl)-2-oxoethylidene]hydrazinyl}-4-aryl(hetaryl)-4-oxobut-2-enoic acids which were shown to exist in solution as mixtures of Z- and E-isomeric enehydrazine tautomers. The products underwent cyclization to 3-{[2-(3-R-adamantan-1-yl)-2-oxoethylidene]- hydrazinylidene}-5-aryl(hetaryl)furan-2(3H)-ones.     

New bis-, tris- and tetrakis(pyrazolyl)borate ligands with 3-pyridyl and 4-pyridyl substituents: synthesis and coordination chemistry

The new ligands dihydrobis[3-(4-pyridyl)pyrazol-1-yl]borate [Bp(4py)]-, hydrotris[3-(4-pyridyl)pyrazol-1-yl]borate [Tp(4py)]-, tetrakis[3-(4-pyridyl)pyrazol-1-yl]borate [Tkp(4py)]-, dihydrobis[3-(3-pyridyl)pyrazol-1-yl]borate [Bp(3py)]-, hydrotris[3-(3-pyridyl)pyrazol-1-yl]borate [Tp(3py)]- and tetrakis[3-(3-pyridyl)pyrazol-1-yl]borate [Tkp(4py)]- are derivatives of the well known bis-, tris- and tetrakis-(pyrazolyl)borate cores, bearing 4-pyridyl or 3-pyridyl substituents attached to the pyrazolyl C3 positions. These pyridyl groups cannot chelate to the metal ions in the poly(pyrazolyl) cavity but are externally directed. Structural studies on a range of metal complexes show how, in many cases, coordination of these pendant pyridyl groups to the M(pyrazolyl)n core of an adjacent metal complex fragment results in formation of coordination oligomers or polymeric networks. [Tl(Bp(3py))], [Tl(Bp(4py))] and [Tl(Tp(4py))] form one-dimensional polymeric chains via coordination of one of their pendant pyridyl units to the Tl(I) centre of an adjacent complex fragment; in contrast, in [Tl(Tp(3py))] coordination of all three pendant pyridyl units to separate Tl(I) neighbours results in formation of a two-dimensional polymeric sheet. In [Tl(Tkp(3py))] and [Tl(Tkp(4py))] the Tl(I) is coordinated by two or three of the four pyrazolyl arms, respectively; bridging interactions of pendant 4-pyridyl groups with adjacent Tl(I) centres result in a two-dimensional sheet forming in each case. In Ag(Tkp(4py)) each Ag(I) ion is coordinated by two pyrazolyl rings, and two bridging pyridyl ligands from other complex units, resulting in a one-dimensional chain consisting of pairs of cross-linked zigzag chains. In contrast to these polymeric coordination networks, the structures of [Cu(Tp(4py))] and [(Tp(3py))Cd(CH3CO2)] are dimers, with a pendant pyridyl residue from the first metal centre attaching to a vacant coordination site on the second, and vice versa; these dimers are stabilised by pi-stacking interactions between sections of the two ligands. [Ni(Tp(3py))2] is monomeric, with an octahedral coordination geometry arising from two tris(pyrazolyl)borate chelates; the array of pendant 3-pyridyl groups is involved only in intramolecular hydrogen-bonding. [(Tp(4py))Re(CO)3] is also monomeric, with a facial arrangement of three pyrazolyl ligands and three carbonyls, with the pendant 4-pyridyl groups not further coordinated. [(Tp(2py))Re(CO)3], based on the related ligand hydrotris[3-(2-pyridyl)pyrazol-1-yl]borate, has a similar fac-(CO)3(pyrazolyl)3 coordination geometry.     

Reactions of 4-Chloro-3-formylcoumarin with Arylhydrazines

The interaction of 3-formyl-4-coumarin with arylhydrazine hydrochlorides in the presence of sodium acetate gave the corresponding 3-arylhydrazonomethyl-4-chlorocoumarin, and with phenylhydrazine, 4-bromo- and 4-chlorophenylhydrazine hydrochlorides in the presence of two equivalents of triethylamine gave either 1-aryl- or 2-aryl[1]benzopyrano[4,3-c]pyrazol-4-ones depending on the reaction conditions. In reactions of 4-chloro-3-formylcoumarin with 2,4-dichloro-, 2,4-difluoro-, 2-hydroycarbonyl-, 4-nitro- and 3,5-di(trifluoromethyl)phenylhydrazine, 2-pyridyl- and 2-quinoxalylhydrazine in the presence of excess of triethylamine the 2-aryl[1]benzopyrano[4,3-c]pyrazol-4(2H)-ones were obtained exclusively. The structures of 1-phenyl- and 2-(2-pyridyl)[1]benzopyrano[4,3-c]pyrazolo-4(1H)ones were confirmed by X-ray crystallography. A simple method is proposed to distinguish between 1- and 2-substituted [1]benzopyrano[4,3-c]pyrazolo-4-ones on the basis of the ¹H NMR chemical shifts of the C(3)-H proton in two solvents - DMSO-d₆ and CDCl₃.     

Synthesis and tautomerism of 2-[3(5)-aryl(methyl)pyrazol-4-yl]-1-benzimidazoles

An efficient method has been developed for the synthesis of 2-[3(5)-aryl(methyl)pyrazol-4-yl]-1H-benzimidazoles by cyclocondensation of 2-acylmethyl-1H-benzimidazoles benzoylhydrazones with DMF dimethylacetal. The tautomerism of the compounds obtained via migrations of a proton between the pyrazole nitrogen atoms has been studied by ¹H NMR. The more stable tautomers have electron acceptor aryl substituents placed at position 3 of the pyrazole ring and electron donor aryl substituents or a methyl at position 5. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1370–1377, September, 2006.     

4-Functionally Substituted 3-Heterylpyrazoles: VII. 3-Aryl(heteryl)-1-phenyl-4-pyrazolecarbonyl Isothiocyanates

3-Aryl(heteryl)-1-phenyl-4-pyrazolecarbonyl isothiocyanates were synthesized by treatment of 3-aryl(heteryl)-1-phenyl-4-pyrazolecarbonyl chlorides with lead, sodium, or ammonium thiocyanate. Their reactions with amines, hydrazines, and acylhydrazines gave the corresponding thioureas and thiosemi- carbazides.     

Synthesis of methyl 9-(benzo[<Emphasis Type="Italic">d</Emphasis>][1,3]dioxol-5-yl)-12-aryl(heteryl,cyclohexenyl)-11-oxo-7,8,9,10,11,12-hexahydrobenzo[<Emphasis Type="Italic">b</Emphasis>][4,7]phenanthroline-10-carboxylates

By condensation of 6-aminoquinoline with methyl 2-(benzo[d][1,3]dioxol-5-yl)-4,6-dioxocyclohexanecarboxylate and aldehydes of aromatic, heteroaromatic, and cyclohexene series new 4,7-phenanthroline derivatives were synthesized. The reaction performed in 1-butanol proceeded regiospecifically and with a moderate degree of stereoselectivity resulting in a mixture of cis- and trans-methyl 9-(benzo-[d][1,3] dioxol-5-yl)-12-aryl(heteryl, cyclohexenyl)-11-oxo-7,8,9,10,11,12-hexahydrobenzo-[b][4,7]-phenanthroline-10-carboxylates (∼30: 70).     

2D and 3D Cu(hfac)2 complexes with nitronyl nitroxide biradicals

Reactions between Cu(hfac)2 and nitronyl nitroxide biradicals 1,4-bis[4-(4,4,5,5-tetramethyl-3-oxide-1-oxyl-4,5-dihydro-1H-imidazol-2-yl)pyrazol-1-yl]butane (L4) and 1,8-bis[4-(4,4,5,5-tetramethyl-3-oxide-1-oxyl-4,5-dihydro-1H-imidazol-2-yl)pyrazol-1-yl]octane (L8) gave respectively a framework compound [Cu(hfac)2]2L4 and a layered polymer compound [Cu(hfac)2]2L8. The framework of [Cu(hfac)2]2L4 consists of 66-membered condensed metallocycles. Inside the framework, the structure has macrohelixes (pitch approximately 25 A) extending along the [001] crystallographic direction. All the helixes have the same direction of winding; the crystals, therefore, are optically active, the structure corresponding either to P-isomer (P4(1)2(1)2) or to M-isomer (P4(3)2(1)2). The long distances between the Cu atoms and the O atoms of the coordinated >N-O groups (Cu-O 2.351-2.467 A) are responsible for ferromagnetic exchange interactions in Cu2+-O-N< and >N-O-Cu2+-O-N< exchange clusters.     

4-Functionally Substituted 3-Heterylpyrazoles: XIII. 3-Aryl(heteryl)-4-(4-pyrazolyl)-1,2,3,4-tetrahydropyrimidin-2-ones(thiones)

Cyclocondesation of 3-aryl(heteryl)pyrazole-4-carbaldehydes with ethyl acetoacetate and urea (thiourea) in the presence of FeCl₃ · 6H₂O afforded 3-aryl(heteryl)-4-(4-pyrazolyl)-1,2,3,4-tetrahydropyrimidin-2-ones(thiones).__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 1, 2005, pp. 97–98.Original Russian Text Copyright © 2005 by Bratenko, Chornous, Vovk.     

4-functionally substituted 3-hetarylpyrazoles: XX. Synthesis of derivatives of 5-(pyrasol-4-yl)-1,2,4-triazole and 3-(pyrazol-4-yl)-1,2,4-triazolo[3,4-c][1,4]oxazine

N-Methylimines of 3-aryl-1-phenylpyrazole-4-carbaldehyde react with ethyl 2-aryl-hydrazino-2-chloroacetate with the formation of ethyl 1-aryl-5-(pyrazole-4-yl)-4,5-dihydro-1H-1,2,4-triazolecarboxylates. Analogous reactions of pyrazol-4-carbaldehyde N-(2-hydroxy)ethylimines results in derivatives of 3-(pyrazol-4-yl)-1,2,4-triazolo[3,4-c][1,4]-oxazines.     

2-R-5-Ar(Het)-5,6-dihydro-7H-[1,2,4]triazolo[5,1-b][1,3]thiazin-7-ones

A novel method for synthesis of 2-R-5-Ar(Het)-5,6-dihydro-7H-[1,2,4]triazolo[5,1-b][1,3]thiazin-7-ones by condensation of 3-R-4,5-dihydro-1H-1,2,4-triazole-5-thiones with 3-aryl(heteryl)-2-propenoyl chlorides is proposed.