Synthesis and structure of (bis(3,5-dimethyl-1<Emphasis Type="Italic">H</Emphasis>-pyrazol-1-yl)methane)diiodocobalt(II)

A cobalt(II) iodide complex with bis(3,5-dimethyl-1H-pyrazol-1-yl)methane (L) CoLI₂ has been synthesized, and its single crystals have been obtained. The complex compound was characterized by electron spectroscopy and X-ray diffraction analysis. The compound crystallizes in the monoclinic system (a = 8.4044(4) Å, b = 13.3120(5) Å, c = 14.5824(7) Å; β = 94.7290(10)°; V = 1625.92(13) ų; Z = 4; ρ^calc = 2.112 g/cm³; space group P2₁/m). The structure of the complex is molecular mononuclear. L is a cyclic bidentate ligand; the coordination polyhedron of cobalt is a CoN₂I₂ tetrahedron formed by the nitrogen atoms of the pyrazole fragments L and iodine atoms. The complex has π-π stacking interactions between the pyrazole rings of CoLI₂ molecules, binding the molecules into infinite chains along the b axis.     

Complexes of cobalt(II) halides with 2-(1<Emphasis Type="Italic">H</Emphasis>-pyrazol-1-yl)-4(3<Emphasis Type="Italic">H</Emphasis>)-pyrimidinone

The electronic structures of complexes of cobalt(II) halides with 2-(1H-pyrazol-1-yl)-4(3H)-pyrimidinone have been studied by X-ray photoelectron spectroscopy. The Co2p _3/2 lines of cobalt atoms, N1s lines of nitrogen atoms, and O1s lines of oxygen atoms in the X-ray photoelectron spectra have been analyzed. Based on these data for the free and coordinated ligands, the atoms of the ligand coordinated to the central metal atom are determined. The coordinated organic compound serves as an electron-donating ligand. The results obtained are consistent with IR and UV-Vis spectroscopic data.     

3-(4,5-Dihydro-1<Emphasis Type="Italic">H</Emphasis>-pyrazol-1-ylmethyl)oxazolidines and 3-(4,5-dihydro-1<Emphasis Type="Italic">H</Emphasis>-pyrazol-1-ylmethyl)perhydro-1,3-oxazines

3-(4,5-Dihydro-1H-pyrazol-1-ylmethyl)oxazolidines and 3-(4,5-dihydro-1H-pyrazol-1-ylmethyl)perhydro-1,3-oxazines were synthesized in 54–85% yield by reactions of α-amino alcohols and 3-aminopropan-1-ol, respectively, with formaldehyde and 4,5-dihydro-1H-pyrazoles.     

Regioselective synthesis of polyfluoroalkyl-substituted 7-(1<Emphasis Type="Italic">H</Emphasis>-1,2,3-triazol-1-yl)-6,7-dihydro-1<Emphasis Type="Italic">H</Emphasis>-indazol-4(5<Emphasis Type="Italic">H</Emphasis>)-ones

3-Polyfluoroalkyl-6,6-dimethyl-7-(1H-1,2,3-triazol-1-yl)-6,7-dihydro-1H-indazol-4(5H)-ones were synthesized with high regioselectivity by 1,3-dipolar cycloaddition of terminal alkynes (phenylacetylene, hex- 1-yne, hept-1-yne, and but-3-yn-1-ol) to 7-azido-6,6-dimethyl-3-polyfluoroalkyl-6,7-dihydro-1H-indazol-4(5H)-ones which were prepared by bromination of 6,6-dimethyl-3-polyfluoroalkyl-6,7-dihydro-1H-indazol- 4(5H)-ones with N-bromosuccinimide in anhydrous carbon tetrachloride, followed by treatment of the corresponding 7-bromo derivatives with sodium azide.     

Electrophilic cyclization of <Emphasis Type="Italic">N</Emphasis>-allyl(propargyl)-5-amino-1<Emphasis Type="Italic">H</Emphasis>-pyrazole-4-carboxamides. Synthesis of 4-[(dihydro)oxazol-2-yl]-1<Emphasis Type="Italic">H</Emphasis>-pyrazol-5-amines

N-Allyl-5-amino-1H-pyrazole-4-carboxamides in reactions with polyphosphoric acid, with N-halosuccinimides in chloroform, and with (chlorosulfanyl)benzenes in nitromethane in the presence of lithium perchlorate underwent cyclization involving the N-allylamide fragment to give 4-[5-methyl(halomethyl)-4,5-dihydrooxazol-2-yl]-1H-pyrazol-5-amines and 2-(5-amino-1H-pyrazol-4-yl)-5-[(arylsulfanyl)methyl]-4,5-dihydro-1,3-oxazolium perchlorates, respectively. Analogous reactions of N-propargyl-5-amino-1H-pyrazole-4-carboxamides with polyphosphoric acid afforded 4-(5-methyloxazol-2-yl)-1H-pyrazol-5-amines, and with (chlorosulfanyl) benzenes, 2-(5-amino-1H-pyrazol-4-yl)-5-[(arylsulfanyl)methylidene]-4,5-dihydro-1,3-oxazolium perchlorates.     

Aqueous hydrolysis of 3-[2-(3-methyl-1<Emphasis Type="Italic">H</Emphasis>-pyrazol-1-yl)-ethylamino]-and 3-[2-(5-methyl-1<Emphasis Type="Italic">H</Emphasis>-pyrazol-1-yl)ethylamino]-propanoates

Noncatalytic hydrolysis of methyl 3-[2-(3-methyl-1H-pyrazol-1-y)ethylamino]-and methyl 3-[2-(5-methyl-1H-pyrazol-1-yl)ethylamino]propanoates at 200°C was performed. According to X-ray diffraction data, the resulting acids exist exclusively as salts.     

Synthesis and reactions of 3-(3-ethoxycarbonyl-1-phenyl-1<Emphasis Type="Italic">H</Emphasis>-pyrazol-4-yl)propenic acid

The reaction of ethyl 4-formyl-1-phenyl-1H-pyrazole-3-carboxylate with the malonic acid led to the formation (2E)-3-(3-ethoxycarbonyl-1-phenyl-1H-pyrazol-4-yl)propenic acid. In reactions of this acid chloride with 4-amino-5-aryl(hetaryl)-4H-1,2,4-triazole-3-thiols were obtained ethyl 4-[(E)-2-{3-aryl(hetaryl)[1,2,4]triazolo[3,4-b][1,3,4]thiadiazol-6-yl}ethenyl]-1-phenyl-1H-pyrazoe-3-carboxylates, with 5-aryltetrazoles, ethyl 4-[(E)-2-(5-aryl-1,3,4-oxadiazol-2-yl)-ethenyl]-1-phenyl-1H-pyrazole-3-carboxylates, with 1-(2-hydroxy-3,5-dimethylphenyl) followed by the Baker-Venkataraman rearrangement and the cyclization, ethyl 4-[(E)-2-(6,8-dimethyl-4-oxo-4Hchromen-2-yl)ethenyl]-1-phenyl-1H-pyrazole-3-carboxylate.     

Synthesis and fungicidal activity of bis(2-arylcarbonylamino-1<Emphasis Type="Italic">H</Emphasis>-benzimidazol-5-yl) sulfones

A procedure has been developed for the synthesis of bis(2-arylcarbonylamino-1H-benzimidazol-5-yl) sulfones by reaction of the corresponding substituted benzoyl chloride with sodium cyanamide and subsequent treatment of the N-cyanobenzamide thus formed with 3,3′,4,4′-tetraaminodiphenyl sulfone in acid medium. The products were tested for fungicidal activity.     

Reaction 5-(Arylmethylidene)pyrimidine-2,4,6(1<Emphasis Type="Italic">H</Emphasis>,3<Emphasis Type="Italic">H</Emphasis>,5<Emphasis Type="Italic">H</Emphasis>)-triones with L-Proline and Aldehydes

Boiling in toluene of 5-(arylmethylidene)pyrimidine-2,4,6(1H,3H,5H)-triones with L-proline and aldehyde led to the formation of previously unknown substituted 1′-arylhexahydro-1H-spiro[pyrimidine-5,2′-pyrrolysine]-2,4,6(1H,3Н,5Н)-triones.     

Synthesis and structure of potassium 2-(pyridin-2-yl)-1<Emphasis Type="Italic">H</Emphasis>-benzo[<Emphasis Type="Italic">d</Emphasis>]imidazolate and preparation of related bis(diimine) ligands

A potassium derivative of 2-(pyridin-2-yl)-1H-benzo[d]imidazole (BenzimidK) is synthesized and structurally characterized (СIF file CCDC no. 1478559). The complex is used for the preparation of new bis(diimine) ligands containing different diimine fragments linked by the bridging (CH₂)₄ group.     

Synthesis and study of macroheterocyclic compounds derived from 1<Emphasis Type="Italic">H</Emphasis>-phenalene-1,3(2<Emphasis Type="Italic">H</Emphasis>)-diimine

Symmetrical macroheterocyclic compounds are synthesized by the reaction of 1H-phenalene-1,3(2H)-diimine with m-phenylenediamine, 2,6-diaminopyridine, and 2,5-diamino-1,3,4-thiadiazole. IR and UV spectral data are given.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 8, 2004, pp. 1355–1359.Original Russian Text Copyright © 2004 by Berezina, Vorobev, Vorobeva, Andreikina.This revised version was published online in April 2005 with a corrected cover date.     

Microwave assisted synthesis of substituted (<Emphasis Type="Italic">Z</Emphasis>)-2-{[1-phenyl-3-(thiophen-2-yl)-1<Emphasis Type="Italic">H</Emphasis>-pyrazol- 4-yl]methylene}benzofuran-3(2<Emphasis Type="Italic">H</Emphasis>)-ones and their antimicrobial activity

Aurones, pyrazole and thiophene scaffolds are known for their potential antimicrobial activity. Herein, we have synthesized hybrid compounds containing three substituted (Z)-2-{[1-phenyl-3-(thiophen-2-yl)- 1H-pyrazol-4-yl]methylene}benzofuran-3(2H)-ones that had been produced from substituted (E)-1-(2-hydroxyphenyl)- 3-[1-phenyl-3-(thiophen-2-yl)-1H-pyrazol-4-yl]prop-2-en-1-ones in high yields. All synthesized compounds were tested in vitro for their antimicrobial activity. Several of those demonstrated promising activity against some fungal and bacterial strains.     

Regioselectivity in the reactions of <Emphasis Type="Italic">N</Emphasis>-(polychloroethylidene)-sulfonamides with 1<Emphasis Type="Italic">H</Emphasis>-pyrrole and 1-methyl-1<Emphasis Type="Italic">H</Emphasis>-pyrrole

N-(2,2,2-Trichloroethylidene)arenesulfonamides react with 1H-pyrrole and 1-methyl-1H-pyrrole to give the corresponding N-[2,2,2-trichloro-1-(1H-pyrrol-2-yl)ethyl]arenesulfonamides. The reaction of N-(2,2,2-trichloroethylidene)trifluoromethanesulfonamide with pyrrole leads to a mixture of 2-mono-and 2,5-disubstituted pyrroles, whereas in the reaction with 1-methyl-1H-pyrrole only the 2-substituted compound is formed. N-(2,2-Dichloro-2-phenylethylidene)-4-methylbenzenesulfonamide reacts with 1H-pyrrole to form N-[2,2-dichloro-2-phenyl-1-(1H-pyrrol-2-yl)ethyl]-4-methylbenzenesulfonamide, and its reaction with 1-methyl-1H-pyrrole gives a mixture of 2-and 3-monosubstituted derivatives. The results of quantum-chemical calculations of the initial reactants and products indicate that the process is orbital-controlled. A good agreement is observed between the experimental data and theoretical conclusions concerning the dependence of the reaction regioselectivity on the nature of substituents in the electrophile molecule.     

Synthesis of 7-(furan-2-yl)-7,8,10,10a-tetrahydro-6<Emphasis Type="Italic">H</Emphasis>-benzo[<Emphasis Type="Italic">c</Emphasis>]-chromen-6,9(6a<Emphasis Type="Italic">H</Emphasis>)-diones

Methods of synthesis were developed for 7-(furan-2-yl)-substituted 7,8,10,10a-tetrahydrobenzo[c] chromen-6,9-diones by regioselective [4+2]-cycloaddition of coumarin-3-carboxylic acids to 2-(3-trimethylsiloxybuta- 1,3-dien-1-yl)furans. The [4+2]-cycloaddition was efficiently catalyzed with L-proline.     

Three-component heterocyclization of 5-(arylmethylidene)pyrimidine-2,4,6(1<Emphasis Type="Italic">H</Emphasis>,3<Emphasis Type="Italic">H</Emphasis>,5<Emphasis Type="Italic">H</Emphasis>)-triones with aldehydes and amino acids

Previously unknown substituted 4-aryl-2,7,9-triazaspiro[4.5]decane-6,8,10-triones were synthesized in 50–70% yield by heating 5-(arylmethylidene)barbituric acids with N-methyl- or N-phenylglycine and para-formaldehyde or 4-methoxybenzaldehyde in boiling toluene for 14 h.     

Recyclization of 1,3-dialkyl-6-nitro-1<Emphasis Type="Italic">H</Emphasis>-imidazo[4,5-<Emphasis Type="Italic">b</Emphasis>]pyridine-2,5(3<Emphasis Type="Italic">H</Emphasis>,4<Emphasis Type="Italic">H</Emphasis>)-diones into imidazole derivatives

Treatment of 5-amino-1,3-dialkyl-2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-ones with sodium nitrite in aqueous HCl gave 1,3-dialkyl-1H-imidazo[4,5-b]pyridine-2,5(3H,4H)-diones which were nitrated with potassium nitrate in sulfuric acid to 6-nitro derivatives, and the latter underwent recyclization into 4-amino-1,3-dialkyl-5-(1H-pyrazol-5-yl)-2,3-dihydro-1H-imidazol-2-ones by the action of hydrazine hydrate.     

7,8,9-trimethyl-1-phenyl-3<Emphasis Type="Italic">H</Emphasis>-pyrrolo[2,1-<Emphasis Type="Italic">d</Emphasis>][1,2,5]triazepin-4(5<Emphasis Type="Italic">H</Emphasis>)-one. Synthesis and reactions

A strategy was developed for the synthesis of 7,8,9-trimethyl-1-phenyl-3H-pyrrolo[2,1-d][1,2,5]-triazepin-4(5H)-one, reactions of its functionalization at the С⁴ atom and aza rings fusion at the С⁴?N³ bond were explored. The formation mechanism of the pyrrolo-1,2,5-triazepinone scaffold was suggested.     

Synthesis,structure, and stereochemical non-rigidity of bis[(2,2-dimethyl-4-oxo-2<Emphasis Type="Italic">H</Emphasis>-benzo[<Emphasis Type="Italic">e</Emphasis>][1,3]oxazin-3(4<Emphasis Type="Italic">H</Emphasis>)-yl)methyl] dichlorosilane and -germane

Bis[(2,2-dimethyl-4-oxo-2H-benzo[e][1,3]oxazin-3(4H)-yl)methyl]dichlorosilane (1) and -germane (2) were synthesized by the reaction of 2,2-dimethyl-3-(trimethylsilyl)-2H-benzo[e][1,3]oxazin-3(4H)-one with bis(chloromethyl)dichlorosilane and -germane, respectively, taken in a ratio of 2 : 1. The structures of these compounds were determined and their stereodynamic behavior in solution was studied by multinuclear (¹H, ¹³C, and ²⁹Si) and twodimensional (¹H, ¹³C COSY, HETCOR) NMR spectroscopy. The ²⁹Si NMR spectroscopic study of a solution of complex 1 provides evidence that the silicon atom in this complex is pentacoordinate. The X-ray diffraction study showed that the germanium atom in complex 2 in the solid state is hexacoordinate. The permutation isomerization in the coordination units of complexes 1 and 2 was found and investigated by dynamic ¹H NMR spectroscopy. Different mechanisms of stereodynamic transformations are suggested and discussed.     

Synthesis and antimicrobial screening of novel 9-{2-[(1<Emphasis Type="Italic">H</Emphasis>-1,2,3-triazol-4-yl)methoxy]phenyl}-3,3,6,6-tetramethyl-3,4,5,6,7,9-hexahydro-1<Emphasis Type="Italic">H</Emphasis>-xanthene-1,8(2<Emphasis Type="Italic">H</Emphasis>)-dione derivatives

A series of novel 9-{2-[(1H-1,2,3-triazol-4-yl)methoxy]phenyl}-3,3,6,6-tetramethyl-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione derivatives were synthesized by a click chemistry approach. The structures of all the newly synthesized compounds were characterized by IR, MASS, ¹H and ¹³C NMR spectral data. The final analogues showed good to excellent antibacterial and antifungal activities in an agar well diffusion assay. Compounds 6i and 6f were the most active against all the test bacterial and fungal strains.