Interaction of (z)-4-bromo-1,3-di(2-thienyl)- 2-buten-1-one with amines,synthesis of di(2-thienyl)azolo[<Emphasis Type="Italic">a</Emphasis>]pyridines

(Z)-4-Bromo-1,3-di(2-thienyl)-2-buten-1-one was obtained by the bromination of 1,3-di(2-thienyl)-2-buten-1-one by NBS in anhydrous CCl₄. The starting butanone was obtained by the condensation of 1-(2-thienyl)-1-ethanone by the action of SOCl₂. The reaction of (Z)-4-bromo-1,3-di(2-thienyl)-2-buten-1-one with tertiary amines such as Et₃N, pyridine, 1-alkyl-1,3-diazole, 1-alkylbenzimidazole, and 1-alkyl-1,2,4-triazole leads to quaternary salts. The azolium salts cyclize by the action of base to give di(2-thienyl)azolo[a]pyridinium derivatives. 3-Methyl-6,8-di(2-thienyl)[1,3]thiazolo[3,2-a]pyridin-4-ium and 2,4-di(2-thienyl)pyrido[2,1-b]benzothiazol-10-ium bromides were obtained by the same procedure but without separating the intermediate quaternary salts.     

Reactions of (1R,2S)-1,2-di(2-furyl)-1,2-di(3-guaiazulenyl)ethane and (1R,2S)-1,2-di(3-guaiazulenyl)-1,2-di(2-thienyl)ethane with tetracyanoethylene (TCNE) in benzene: comparative studies on the products and their spectroscopic properties

Reactions of the title meso forms, (1R,2S)-1,2-di(2-furyl)-1,2-di(3-guaiazulenyl)ethane (1) and (1R,2S)-1,2-di(3-guaiazulenyl)-1,2-di(2-thienyl)ethane (2), with a two molar amount of TCNE in benzene at 25 °C for 5 h (for 1) and 48 h (for 2) under oxygen give new compounds, 2,2,3,3-tetracyano-4-(2-furyl)-8-isopropyl-6-methyl-1,4-dihydrocyclohepta[c,d]azulene (3) and 2,2,3,3-tetracyano-8-isopropyl-6-methyl-4-(2-thienyl)-1,4-dihydrocyclohepta[c,d]azulene (4), respectively, in 74 and 21% isolated yields. Comparative studies on the above reactions as well as the spectroscopic properties of the unique products 3 and 4, possessing interesting molecular structures, are reported and, further, a plausible reaction pathway for the formation of these products is described.     

The first synthesis of dihydro-3H-pyrido[2,3-b][1,4]diazepinols and a new alternative approach for diazepinone analogues

The first synthesis of a series of 2-aryl(heteroaryl)-4-trifluoromethyl-4,5-dihydro-3H-pyrido[2,3-b][1,4]diazepin-4-ols, where aryl = C₆H₅, 4-FC₆H₄, 4-ClC₆H₄, 4-BrC₆H₄, 4-CH₃C₆H₄, 4-OCH₃C₆H₄, 4,4′-biphenyl, 1-naphthyl and heteroaryl = 2-thienyl, 2-furyl obtained from the direct cyclocondensation reaction of 4-methoxy-1,1,1-trifluoroalk-3-en-2-ones with 2,3-diaminopyridine in 54-71% yield, is reported. Another alternative and efficient route for the synthesis of a series of 2-aryl(heteroaryl)-3H-pyrido[2,3-b][1,4]diazepin-4(5H)-ones from the reaction 4-methoxy-1,1,1-trichloroalk-3-en-2-ones with 2,3-diaminopyridine, in 54-70% yield, is also reported.     

Coupling and Cyclization of Sydnone Compounds

Cyclization were occurred via the coupling reactions of some mercuric chloride derivatives of sydnone with LiPdCl₃-CuCl₂. A unique six-membered ring, 3,3′-ethylene-4,4′-bissydnone, was obtained by the cyclization reation of 1,2-di[3-(4-chloromercuric)sydnonyl]ethane. However, the seven-membered 3,3′-trimethylene-4,4′-bissydnone and 1,3-di[3-(4-chloro)sydnonyl]-propane were obtained from the corresponding mercuric chlroide of sydnone. Onyl substitution reaction took place when 4,4′-di[3-(4-chloromercuric)sydnonyl]biphenyl, 4,4′-di[3-(4-chloromercuric)sydnonyl]benzene, di(p-[3-(4-chloromercuric)sydnonyl]-phenyl}methane and, di(p-[3-(4-chloromercuric)sydnonyl]phenyl]ether were treated using the same process.     

Synthesis and optical properties of conjugated N,N-dimethyl and thienyl end-capped 2,5-(arylethynyl)thiophene oligomer structures

End-capped (N,N-dimethylaminophenyl) and 2′-thienylethynyl 2,5-thiophene oligomer structures were synthesized by heterocoupling between the terminal acetylenes such as: p-(N,N-dimethylaminophenyl)ethyne (3) [or 1-(p-(N,N-dimethylaminophenyl)-2-p-(ethynylphenyl)ethyne, 4]; p-(β-ethenyl-2′-thienyl)phenylethyne (E-9) [or p-(β-ethynyl-2′-thienyl)phenylethyne, 11], and 2,5-diiodothiophene, catalyzed by the Cl₂Pd(PPh₃)₂/CuI system, in good to excellent yields. The 2,5-di[(3′,5′-di(trimethylsilylethynyl)phenyl]_x-1-ethynyl]thiophene oligomers were prepared by heterocoupling between 3′,5′-di[(trimethylsilylethynyl)phenyl]_x-1-ethyne (n = 0-2) terminal acetylenes and 2,5-diiodothiophene, in excellent yields. The terminal acetylenes were efficiently prepared by a specific protection-deprotection methodology. All the ethynylphenyl compounds obtained show fluorescence radiation emission, with a bathochromic shift of the wavelength that increases with the chain conjugation.     

In Process Citation

The behaviour of two organic compounds, 1,5-di[2-furyl]-1,4-pentadien-3-one (DFPO) and 1,5-di[2-thienyl]-1,4-pentadien-3-one (DTPO), as acid-base indicators has been studied by plotting the curves A = f(lambda) in the presence of various concentrations of perchloric acid, in anhydrous acetic acid medium. The values of pK(i)(HClO(4))) have been determined by spectrophotometry. The efficiency of these indicators in visual and colorimetric detection of the end-points of acid-base titrations has been examined.     

Synthesis of conjugated 2 and 2,5-(ethenyl) and (ethynyl)phenylethynyl thiophenes: fluorescence properties

Nano conjugated thienylethenyl and thienylethynyl compounds with controlled structure and dimensions have been efficiently prepared, by heterocoupling reaction between 1,4-(thienylethynyl)phenylacetylene (or thienylethenyl)phenylacetylene and 2- or 2,5-dihalothiophene. Conjugated 1,4-di(2-thienylethynylphenyl)- (or 2-thienylethenylphenyl)-1,3-butadiyne were obtained by the homocoupling of the terminal acetylenes in excellent yield. The end-capped (N,N-dimethylaminophenyl)- and [3,5-di(trimethylsilylethynyl)-1-ethynyl]-2,5-di(phenylethynyl)_nthiophene were obtained by the heterocoupling between the corresponding terminal acetylene and 2,5-di(iodo)thiophene, catalyzed by the bis(triphenylphosphine)palladium and cuprous iodide system in excellent yield.     

Synthesis of cyclic polysulfides by the reaction of trimethylvinylsilane with S8 in the presence of Fe3(CO)12

Reaction of trimethylvinylsilane with S₈ in the presence of Fe₃(CO)₁₂ yielded the following compounds: S₂Fe₂(CO)₆, S₂Fe₃(CO)₉, 1-trimethylsilyl-2,3,4,5,6-pentathiacycloheptane, 1,4-di(trimethylsilyl)-2,3,6-trithiacycloheptane, 1,4-di(trimethylsilyl)-2,3,6,7-tetrathiacyclooctane. An X-ray analysis was performed for the two latter polysulfides.     

Complexes of copper(II) with diazabutadienes

Summary Studies on the chelate complexes of copper(II) with the bidentate ligands, 1,4-diphenyl-2,3-dimethyl-1,4-diazabutadiene (PMB) and 1,4-di(p-methoxyphenyl)-2,3-dimethyl-1,4-diazabutadiene (MPMB), have been carried out. On the basis of the elemental analysis and molar conductivity, the complexes have been characterized as [Cu(PMB)Cl₂], [Cu(PMB)₂](ClO₄)₂, [Cu(MPMB)Cl₂] and [Cu(MPMB)₂](ClO₄)₂. Both diazabutadienes are bidentate via nitrogen atoms. The temperature dependence of the magnetic susceptibility and the electron paramagnetic resonance, i.r. and u.v.-vis spectra are reported. All compounds appear to be monomers.     

The electrochemical properties of a series of phenylene-thienyl polymers in tetramethylene sulfone based electrolytes

Electronically conducting polymers based on polythiophene and polyparaphenylene exhibit generally, both n-doping and p-doping. In most cases, however, the n-doping process is associated usually with poor reversibility and stability. One approach to improve the doping behavior is to modify the structure of the monomer repeat unit at the molecular level. In this paper we report on the electrochemical properties of the polymer series: pTHP, pTFP (1,4-bis(2-thienyl)-2-fluorobenzene), pTF₂P (1,4-bis(2-thienyl)-2,5-difluorobenzene), and pTF₄P (1,4-bis(2-thienyl)-2,3,5,6-tetrafluorobenzene) in tetramethylene sulfone (sulfolane) TBABF₄ based electrolytes.     

Iron pentacarbonyl assisted photochemical route to 2,5- and 2,6-divinyl-substituted 1,4-benzoquinones from 1-ene-3-ynes

Photochemical reaction between the enynes, (Z)-1-methoxybut-1-ene-3-yne, 1 or isopropenyl acetylene, 2 with CO in presence of Fe(CO)₅ yields the 2,6- and 2,5-divinyl-substituted 1,4-benzoquinones: 2,6-bis{(Z)-2-methoxyvinyl}-1,4-benzoquinone (3, 42%), 2,5-bis{(Z)-2-methoxyvinyl}-1,4-benzoquinone (4, 31.5%), [{η²,η²:2,6-di(prop-1-en-2-yl)-1,4-benzoquinone}tricarbonyliron] (5, 45%), and {η²,η²:2,5-di(prop-1-en-2-yl)-1,4-benzoquinone}tricarbonyliron] (6, 65%).     

A Doubly Interpenetrated Cu(II)-based Metal-Organic Framework as a Heterogeneous Catalyst for the ipso-Hydroxylation of Arylboronic Acids

A doubly interpenetrated Cu(II)-organic framework with formula [{Cu₂( L )₂(4,4′-bpdc)₂(H₂O)₂} ⋅ 8H₂O ⋅ CH₃OH]_α ( 1 ) (where, L =N², N⁶-di(pyridin-4-yl)naphthalene-2,6-dicarboxamide and 4,4′-bpdc=[1,1′-biphenyl]-4,4′-dicarboxylate ion) has been synthesized and characterized with the help of several spectroscopic and analytical techniques including single crystal X-ray analysis. A single crystal X-ray analysis reveals that 1 exhibit interpenetrated two-dimensional sheet-like structure containing elongated channels of cross-section 11.09×31.22 Ų along the a-axis. Finally, 1 has been exploited as a heterogeneous catalyst for the ipso-hydroxylation of arylboronic acids yielding up to 99 % of the respective phenolic product. Importantly, the catalyst can be reused for five successive cycles without having a significant loss in its catalytic efficiency.     

Synthesis of conjugated (1E,3E)- and (1Z,3Z)-1,4-di(n-pyridyl) (or n-quinolyl)-1,3-butadienes from n-(2′-chloroethenyl)pyridine (or quinoline)

The homocoupling reaction between the conjugated n-(2-chloroethenyl)pyridine; n, 2-, 3- and 4- (or quinoline; n, 2- and 4-) mediated by zero-valent nickel complexes at room temperature affords to the corresponding 1,4-diaryl-1,3-butadiene, always as the 1E,3E stereoisomer. The yield in 1,4-diaryl-1,3-butadiene increases with the nickel catalyst and hence, the active zero-valent nickel catalyst is not regenerated during the homocoupling reaction.The stereospecific synthesis of (1Z,3Z)-1,4-di(4′-pyridyl)-1,3-butadiene stereoisomer was efficiently carried out by partial hydrogenation of the appropriate 1,4-di(4′-pyridyl)-1,3-butadiyne.     

Preparations of bis[2-(2-arylethynyl)-3-thienyl]arenes and bis[2-{2-(trimethylsilyl)ethynyl}-3-thienyl]arenes

4,4′-Bis[2-(2-phenylethynyl)-3-thienyl]biphenyl, 4,4′-bis[2-{2-(trimethylsilyl)ethynyl}-3-thienyl]biphenyl and their congeners were prepared and their properties were studied. Extension of π-system through the central benzene ring was suggested by UV-vis spectra. Connection of two 1,4-bis[2-{2-(trimethylsilyl)ethynyl}-3-thienyl]benzene units was exemplified.     

Enamines—XXXIX : Enamines from cyclopropylketones

The enamines from cyclopropyl-methyl-, -ethyl- and -cyclopentylketone have been prepared by reaction of the ketone with a secondary amine and TiCl₄. Their vinylcyclopropane structure has been demonstrated by NMR. The reaction of dicyclopropylketone, cyclopropylphenylketone or cyclopropyl-α-thienylketone with secondary amines and TiCl₄ afforded homoallylic rearrangement products, namely 1-cyclopropyl-, 1-phenyl- and 1-(α-thienyl)-1,4-diamino-1-butene, respectively.     

Unusual Hydrogen-bonding Networks Consisting of π-Extended 4,4′-Bipyridines and Chloranilic Acid

Hydrogen-bonding networks of π-extended 4,4′-bipyridines, 2,5-di(4-pyridyl)thiophene (1), 2,5-di(4-pyridyl)furan (2) and 1,4-di(4-pyridyl)benzene (3) with 2,5-dichloro-3,6-dihydroxy-1,4-benzoquinone (chloranilic acid, CA) have been investigated. The dipyridyl compounds afforded complexes 4 [(dication of 1)·(monoanion of CA)²], 5 [(dication of 2)·(dianion of CA)·(MeOH)] and 6 [(3)·(dication of 3)·(dianion of CA)·(H²O)⁶] with CA. X-ray structure analyses revealed the formation of unusual molecular tape and sheet structures involving N–H ?O, O–H ?O, C–H ?O and N–H ?N hydrogen bonds, where the aromatic spacer groups play an important role in constructing the unique crystal structures.     

Synthesis of conjugated 2-arylethynyl and 2-arylethenyl thiophene structures with optical properties

Conjugated mono(arylethynyl)oligothiophene structures have been obtained starting with (E)-[1-(2′-thienyl)-2-(p-phenyl)]ethyne (E)-7 and 2-[p-(iodophenyl)ethynyl]thiophene 8. Conjugated nanostructures were synthesized by oxidative coupling between the terminal acetylenes (E)-7 and 8 to give, respectively, 1,4-di[(2-p-(iodophenyl)ethynyl)thienyl]-1,3-butadiyne and 1,4-di[(2-p-iodophenylethynyl)thienyl]-1,3-butadiyne. All the thiophene derivatives synthesized show an important fluorescence radiation emission, with a bathochromic shift, which increases with the conjugation of the chain.     

Cross coupling of 3-bromopyridine and sulfonamides (RNHSO2R·R = H, Me, alkyl; R = alkyl and aryl) catalyzed by CuI/1,3-di(pyridin-2-yl)propane-1,3-dione

N-(3-Pyridinyl)-substituted secondary and tertiary sulfonamides have been synthesized in good to excellent yields by the reaction of 3-bromopyridine with primary and secondary alkyl and aryl sulfonamides (MeSO₂NH₂, MeSO₂NHMe, TolSO₂NH₂, TolSO₂NHMe, 1,3-propanesultam, and 1,4-butanesultam), catalyzed by CuI (20 mol %) and 1,3-di(pyridin-2-yl)propane-1,3-dione (20 mol %) with K₂CO₃ (200 mol %) in DMF (0.17 M for ArBr) at 110-120 °C over 36-40 h. 2-Bromopyridine, 4-bromopyridine, and a wide variety of substituted phenyl bromides can also be successfully coupled with sulfonamides under these reaction conditions.     

Organic carboxylate anions effect on the structures of a series of Mn(II) complexes based on 2-phenylimidazo[4,5-f]1,10-phenanthroline ligand

In our efforts to tune the structures of Mn(II) complexes by selection of organic carboxylic acid ligands, six new complexes [Mn(PIP)₂Cl₂] (1), [Mn(PIP)₂(4,4′-bpdc)(H₂O)]·2H₂O (2), [Mn(PIP)₂(1,4-bdc)] (3), [Mn(PIP)(1,3-bdc)] (4), [Mn(PIP)₂(2,6-napdc)]·H₂O (5), and [Mn(PIP)(1,4-napdc)]·H₂O (6) were obtained, where PIP=2-phenylimidazo[4,5-f]1,10-phenanthroline, 4,4′-H₂bpdc=biphenyl-4,4′-dicarboxylic acid, 1,4-H₂bdc=benzene-1,4-dicarboxylic acid, 1,3-H₂bdc=benzene-1,3-dicarboxylic acid, 2,6-H₂napdc=2,6-naphthalenedicarboxylic acid, 1,4-H₂napdc=1,4-naphthalenedicarboxylic acid. All complexes have been structurally characterized by IR, elemental analyses, and single crystal X-ray diffraction. Structural analyses show that complexes 1 and 2 possess mononuclear structures, complexes 3, 4, and 5 feature chain structures, and complex 6 exhibits a 2D (4,4) network. The structural difference of 1–6 indicates that organic carboxylate anions play important roles in the formation of such coordination architectures. Furthermore, the thermal properties of complexes 1–6 and the magnetic property of 4 have been investigated.     

两种3D微孔Zn-MOF对水溶液中Fe3+、Cr2O72-和丙酮分子的荧光传感

通过溶剂热法合成了2种三维微孔锌金属有机框架材料,其分子式为[Zn₃(DBA)(OH)(1,10-phen)₂]_n(1)和{[Zn₂(HDBA)(4,4''-bipy)_1.5]·H₂O}_n(2)(H₅DBA=3,5-二(2'',4''-对羧基苯基)苯甲酸;1,10-phen=1,10-菲咯啉;4,4''-bipy=4,4''-联吡啶)。结构分析表明,配合物1为三核锌基金属单元的三维微孔骨架,配合物2为双核锌基的微孔结构。与2相比,配合物1在水中具有较强的发光性能,可作为检测Fe³⁺、Cr₂O₇^2-和丙酮分子的发光传感器,具有较高的选择性和灵敏度。