Crystal structure of bis-Isonicotinoyl hydrazone of 2,5-diformylpyrrole

bis-Isonicotinoyl hydrazone of 2,5-diformylpyrrole existing in the crystal in the form of a tetrahydrate of the hydrazone tautomeric form is synthesized and its structure is described. In the crystal, an infinite three-dimensional network of hydrogen bonds is formed by hydrazone molecules. The neighboring hydrazone molecules are bonded by intermolecular π stacking interactions. A quantum chemical calculation of the geometry and total energy of possible tautomers in vacuum and an aqueous solution is performed.     

Investigation of the reaction of 1-methyl-2,5-dichloro-3,4-diformylpyrrole with amines

The reaction of 1-methyl-2,5-dichloro-3,4-diformylpyrrole with amines of the aliphatic series leads to products of replacement of one chlorine atom. With aromatic amines the reaction takes place at one of the formyl groups to give aminals. The latter in the presence of excess amine readily give bisazomethines of 1-methyl-2-chloro-5-arylamino-3, 4-diformylpyrrole, which can also be obtained directly by the reaction of dichlorodiformylpyrrole with arylamines. It is shown that in this case one of the formyl groups and the adjacent chlorine atom react initially, after which the second formyl group reacts. The chlorine atom in bisazomethines of 1-methyl-2-chloro-5-arylamino-3,4-diformylpyrrole has high nucleophilic lability and is easily replaced by a hydroxy group or a piperidine residue.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1489–1493, November, 1981.     

Binuclear and polynuclear transition metal complexes with macrocyclic ligands. 4. New polydentate azomethine ligands based on 2,5-diformylpyrrole and 2,6-diformylpyridine

The reactions of 2,5-diformylpyrrole (1) and 2,6-diformylpyridine (2) with propane-1,3-diamine afforded new macrocyclic Schiff"s bases 5 and 6, respectively. Their structures were established by NMR spectroscopy and mass spectrometry. Binuclear copper(ii) and nickel(ii) complexes with ligand 5 were synthesized. Pentadentate Schiff"s base, viz., 2,6-bis[(2-aminophenylimino)methyl]pyridine, was prepared by demetallation of its complex with Cd(ClO₄)₂ using Na₂S. In solutions, the latter Schiff"s base is quantitatively transformed into 2,6-bis(benzoimidazolyl)pyridine under the action of atmospheric oxygen or other mild oxidizing agents.     

Synthesis and characterization of new ferrocenyl bishydrazones

New ferrocenyl bishydrazones (2a–2d) have been efficiently obtained from 1,1′-ferrocenedicarboxaldehyde by a straightforward synthesis. The four new compounds have been fully characterized by NMR (¹H, ¹³C), high-resolution mass spectroscopy, and the molecular structure of compounds (2a–2d) has been elucidated by X-ray diffraction on single crystals.     

New binuclear copper(II) complexes with bishydrazones derived from spiropyran of the benzoxazinonium series

New bishydrazones were prepared from a photochromic spiropyran of the benzoxazinonium series, containing free functional groups in the 2[H]-chromene moiety. This bishydrazones form binuclear complexes with copper(II) ions. The structure of these complexes was studied by ESR spectroscopy and magnetic measurements. The magnetochemical study revealed antiferromagnetic exchange coupling in the complexes.     

New Practical Synthesis of Tetrahydronquinolin-2,5-diones

A series of 4,6,7,8-tetrahydro-2,5-(1H,3H)-quinolinediones was prepared from ethyl-2-cyanoacetate, aromatic aldehydes and 1,3-cyclohexanedione or 5,5-dimethyl-1,3-cyclohexanedione by two steps, the yields were moderate to excellent. This method is a new practical promising green strategy to synthesize tetrahydronquino-lin-2,5-diones.     

Glyoxal bishydrazones through facile ring cleavage of hydrazinopyrazine by hydrazines

The reaction of chloropyrazine and hydrazine was reinvestigated and was shown to produce hydrazinopyrazine and glyoxal bishydrazone. The latter was obtained also when hydrazine hydrochloride was allowed to react with Hydrazinopyrazine. The fusion of hydrazinopyrazine at 160° produced glyoxal his(pyrazinythydrazone). The interconversions of glyoxal bishydrazone with Hydrazinopyrazine were studied. Mechanisms to explain the various transformations are discussed.     

New method for synthesis of 2,5-disubstituted thiophenes

The use of hydrogen sulfide at the moment of formation is proposed for the recyclization of furans into thiophenes in acidic media. The advantages of this method are shown.N. G. Chernyshevskii Saratov State University, Saratov 410026, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 736–738, June, 1999.     

New 2,5-dialkylthio-2-formyl-2,3-dihydro-γ-pyrans

Conclusions A number of new 2,5-dialkylthio-2-formyl-2, 3-dihydro--pyrans was synthesized via the Mannich reaction using alkylthioacetaldehydes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1652–1655, July, 1977.     

2，5-二烷基-1，4-苯二酚类衍生物的新合成方法

研究了合成2，5-二烷基-1，4-苯二酚衍生物的新方法，该方法是以2-取代烷 基1，4-环已二酮为原料，在LiCl催化下，与各种醛缩合反应就得2，5-二烷基-1， 4-苯二酚衍生物，是一种由非芳香环化合物合成2，5-二烷基-1，4-苯二酚衍生物 的新方法。应用该方法简便地合成了天然化合物η-生育酚。     

Synthesis and Reactivity of New 1,1-Diphenyl-2,5-Dihydrophospholium Salts

Abstract

We describe the first synthesis of new 1,1-diphenyl-2,5-dihydrophospholium salts of type 1. These salts allow the access to interesting alkadienyl phosphine oxides 3 and trienes 4. Unfortunately we could not obtain the strong nucleophilic diylide 5.     

New routes for the synthesis of 2,5-disubstituted 4-formylthiazoles

New 2,5-disubstituted 4-formylthiazoles have been obtained by the reaction of acetal-containing -chloroxiranes or their rearrangement products, chloroketones, with thioamides and N-allylurea.Kazan' State Technological University, Kazan' 420015, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 124–129, January, 1998.     

Polymerization behaviour of 2,5-dimethylene- 2,5-dihydrofuran

Spontaneous homopolymerization of 2,5-dimethylene-2,5-dihydrofuran (DDF) was studied. The polymerization rates in two different initial monomer concentrations of DDF were analyzed with the first-order and second-order kinetics, and the homopolymerization of DDF was found to obey the first-order kinetics. The Arrhenius plot of the apparent rate constants at 30, 40, 50, and 60° gave an overall activation energy of 68.0 kJ/mol for the polymerization of DDF. From the comparison of the apparent rate constants at –78° and the time (the so-called half-life time) to decrease in half the monomer concentration for DDF with the corresponding values for p-xylylene (QM), DDF was found to be a less reactive monomer than QM. The copolymerizations of DDF with vinyl monomers such as acrylonitrile (AN), α-chloroacrylonitrile (CIAN), diethyl fumarate (DEF), and fumaronitrile (FN) were carried out in chloroform at 50° in the presence of AIBN to obtain the monomer reactivity ratios r₁(DDF) = 30.0 ± 3.0 and r₂ (AN) = 0 for the DDF-AN system, r₁ (DDF) = 1.55 ± 0.2 and r₂(CIAN) = 0 for the DDF-CIAN system, r₁(DDF) = 3.88 ± 0.2 and r₂(DEF) = 0 for the DDF-DEF system, and r₁(DDF) = 2.41 ± 0.1 and r₂ (FN) = 0 for the DDF-FN system, respectively. As the monomer reactivity ratios of r₂ for all systems were zero, Q and e values of DDF were calculated from the combination of two r₁ (DDF) values of any two copolymerization systems to be the 7.64 to 6.63 ×10²¹ range for Q and the –0.70 to –6.31 range for e, indicating that DDF is a highly conjugative and electron-donating monomer. © 1995 John Wiley & Sons, Inc.     

New method for the synthesis of cis-2,5-disubstituted sulfolane derivatives

A new method for the preparation of functional derivatives of sulfolane by ozonolysis of 13-thiabicyclo[8.2.1]-cis-5-tridecene and its derivatives was developed.Communication III of the series Reaction of Sulfur Halides with Unsaturated Compounds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 360–364, March, 1974.     

Synthesis of Some New 2,4-Disubstituted Hydrazinothiazoles and 2,5-Disubstituted Thiazolidinones

A series of hydrazinothiazoles has been synthesized by the condensation of thiosemicarbazones and α-bromoketones. Similarly the hydrazinothiazolidiones were prepared by the condensation of thiosemicarbazone and α-bromoesters. The newly synthesized compounds were characterized by NMR and LCMS studies.     

Synthesis and metallochromic properties of some new mono- and bishydrazones of benzil and 2,2'-pyridil

Preparation of some new mono- and bishydrazones which possess the ferroin chromophoric group is described, together with results of spectrophotometric studies of their chelation reactions with iron(II), copper(I), cobalt(II), nickel(II) and zinc(II). Several of the new compounds show promise as chromogenic reagents for these metals. The results are also of interest with regard to structure-reaction relationships.     

Catalytic hydroformamination of 2,5-dimethoxy-2,5-dihydrofurans

N-Substituted 3- and 4-formylpyrroles have been obtained by hydroformamination of 2,5-dimethoxy-2,5-dihydrofurans in the presence of HRh(CO)(PPh₃)₃.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1837–1840, August, 1990.