Synthesis and characterization of di- and trivalent pyrazolylborate β-diketonates and cyanometalates

The syntheses, structures, and magnetic properties of a series of di- and trivalent hydridotris(3,5-dimethylpyrazol-1-yl)borate (Tp*) cyanomanganates are described. Treatment of tris(acetylacetonate)manganese(III) [Mn(acac)(3)] with KTp* and tetra(ethyl)ammonium cyanide affords [NEt(4)][(Tp*)Mn(II)(κ(2)-acac)(CN)] (1), as the first monocyanomanganate(II) complex; attempted oxidation of 1 with iodine affords {(Tp*)Mn(II)(κ(2)-acac(3-CN))}(n) (2) as a one-dimensional chain and bimetallic {[NEt(4)][(Tp*)Mn(II)(κ(2)-acac(3-CN))](2)(μ-CN) (3) as the major and minor products, respectively. A fourth complex, [NEt(4)][(Tp*)Mn(II)(η(2)-acac(3-CN))(η(1)-NC-acac)] (4), is obtained via treatment of Mn(acac(3-CN))(3) with KTp* and [NEt(4)]CN, while [NEt(4)](2)[Mn(II)(CN)(4)] (5) was prepared from manganese(II) trifluoromethanesulfonate and excess [NEt(4)]CN. Tricyanomanganate(III) complexes, [cat][(Tp*)Mn(III)(CN)(3)] [cat = NEt(4)(+), 7; PPN(+), 8], are prepared via sequential treatment of Mn(acac(3-CN))(3) with KTp*, followed by [NEt(4)]CN, or [cat](3)[Mn(III)(CN)(6)] with (Tp*)SnBu(2)Cl. Magnetic measurements indicate that 1, 2, and 4 contain isotropic Mn(II) (S = (5)/(2); g = 2.00) centers, and no long-range magnetic ordering is found above 1.8 K. Compounds 7 and 8 contain S = 1 Mn(III) centers that adopt singly degenerate spin ground states without orbital contributions to their magnetic moments.     

Automatically and electronically controllable hydrogel based valves and microvalves – design and operating performance

This paper describes automatically and electronically controlled valves and microvalves based on smart hydrogels. The operating performance of such devices will be discussed in dependence on various design parameters. Furthermore, it will be shown that hydrogel based valves are showing an outstanding possibility of miniaturization, a leakage free switching behavior up to a pressure drop of 8.4 bar, and a pronounced particle tolerance.     

Fluorescence enhancement effect and the interaction between donor and acceptor

A new theoretical equation for fluorescence enhancement effect between donor and acceptor has been introduced.By using it we determined the binding constants and numbers of binding sites of five medicines,including chlorogenic acid,forsythiaside norfloxacin,Ciprofloxacin and fluorenone,to γ-globulin.     

Synthesis and Properties of Polyetherketones Containing Sulfide and Phthalazinone

High molecular weight copoly(ether ketone)s (PEK) based on 4-(4-hydroxyphenyl)-1-phthalazinone (DHPZ)/4,4′-thiobisphenol (TBP)/4,4′-diflourodiphenylketone (DFK) were prepared by nucleophilic substitution polycondensation. The copolymers were characterized by FT- and ^1H-NMR. Thermal properties and solubility of copolymers were studied.     

Donor-Acceptor Oligomers and Polymers Composed of Benzothiadiazole and 3-Hexylthiophene： Effect of Chain Length and Regioregularity

A series of donor-acceptor oligomer OBTThn （n = 1- 7） and polymer PBTThl and PBTTh2 composed of al- ternative 2,1,3-benzothiadiazole and 3-hexylthiophene have been designed and synthesized for the purpose of in- vestigation on the effect of chain length and side-chain regioregularity on their basic properties and photovoltaic performance. In the OBTThn oligomers and PBTThl polymer, all the hexyl side chains on thienyl units orient to- ward the same direction. Upon elongation of the chain length, the intramolecular charge transfer （ICT） absorption band in solution gradually redshifts from 398 nm for OBTThl to 505 nm for OBTThT, then to 512 nm for PBTThl polymer. Meanwhile, the HOMO energy level increases from -5.45 eV （OBTTh0 to -5.08 eV （OBTThT） and -5.09 eV （PBTThl）, and the LUMO energy level decreases from -3.11 eV （OBTTh0 to -3.30 eV （OBTThT） and -3.33 eV （PBTThl）, thus giving a smaller and smaller energy bandgap for higher oligomers and polymers. Theo- retical calculation suggests straight line-like backbone geometry for this series of oligomers and polymer. On the other hand, polymer PBTTh2 possesses a different side-chain regioregularity, in which every two neighbor hexyl side chains are arranged in different orienting direction. It is theoretically suggested to have curved line-like back- bone geometry. In solution, it shows similar photophysical and electrochemical properties as PBTThl. However in film state, it displays a less redshift in the ICT band as refer to that in solution than PBTThl. In combination with [6,6]-phenyl-C61-butyric acid methyl ester （PC61BM）, these oligomers and polymers were used as donor material to fabricate organic bulk heterojunction solar cells. Again, chain length-dependent device photovoltaic performance was observed. The device based on OBTTh4 showed a power conversion efficiency of 0.16%, while it increased to 0.36% and 0.49% for the devices based on OBTTh6 and PBTThb respectively. However, the side-chain regio- regularity has less influence on the device photovoltaic output since the device based on PBTTh~ displayed an effi- ciency of 0.52%, comparable to that of PBTThl.     

Syntheses and characterizations of trinuclear and dinuclear “half-sandwich” zirconocene phosphates and phosphonates

A series of six-coordinate “half-sandwich” zirconocene phosphates and phosphonates have been synthesized by the reaction of Cp₂ZrCl₂ with (diphenyl-, dibenzyl-)phosphate and methylphenylphosphinic acid under different conditions. All of the complexes were characterized by elemental analysis, FT-IR and NMR (¹H, ¹³C) spectroscopy. Except for complex 3, the structures of complexes 1, 2, 4, 5, and 6 were confirmed by X-ray crystallography. The structure analyses reveal that complexes 1, 2, and 3 are trinuclear complexes with fascinating μ₃-oxygen bridging ligands, central to a Zr–O backbone (Cp₂ZrCl₂:ligand is 1:1) while complexes 4, 5, and 6 are centrosymmetric dinuclear complexes built up about the trapezoidal Zr₂(μ₂-OH)₂ unit (Cp₂ZrCl₂:ligand is 1:2).     

Synthesis and electrochemical properties of mono- and (±)-1,2-dialkylferrocenes and alkylferrocenium hexafluorophosphates in aqueous and micellar media

Absract Simple methods have been developed for the preparation of a series ofn-alkylferrocenes H(CH₂) _n Fc (n = 3, 5–8, or 12) based on Friedel-Crafts acylation of ferrocenes followed by reduction of the corresponding ketones with Zn amalgam. The properties of H(CH₂) _n Fc and the corresponding ferrocenium ions in micellar aqueous solutions and the behavior of water-soluble cations H(CH₂) _n Fc⁺ in the absence of micelles were studied by cyclic voltammetry. In all cases, the formal redox potentials of ferrocenes (E ^o) increase linearly asn increases up to 8. Whether micelles are present or not, the corresponding correlation equation has the following form:E ^o= + n, where = 29 mV in all cases. The synthesis of (±)-1-ethyl-2-methylferrocene from racemic -dimethylaminoethylferrocene is reported.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2575–2581, October 1996.     

Synthesis and properties of cross-conjugated ��,�ء�-bis-dimethylamino ketones and dinitriles with N-acetyl- and N-benzylpiperidine cycles

Reactions of N-acetyl- and N-benzyl-4-piperidones with aminal of ??-dimethylaminoac-rolein yielded ketocyanines bearing piperidine cycle. Reaction of 3-dimethylamino-1,1,3-trimethoxypropane with 1-acetylpiperidin-4-ylidenemalononitrile in the presence of ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF₄), resulted in cross-conjugated ??,???-dimethylamino dinitrile. Protonation of ketocyanines bearing N-acetyl- and N-benzyl-piperidine cycles with Et₂O·HBF₄ (1 equiv.) furnished piperidinium salts, while protonation of the latter with Et₂O·HBF₄ (2 equiv.) afforded doubly charged 4-hydroxypolymethine salts. Unlike protonation, reaction of 3,5-bis(3-dimethylaminoprop-2-enylidene)-1-acetylpiperidin-4-one with Me₂SO₄ involved only the oxygen atom and led to a singly charged 4-methoxypolymethine salt. Methylation of 3,5-bis(3-dimethylaminoprop-2-enylidene)-1-benzylpiperidin-4-one with Me₂SO₄ (1 equiv.) involved cyclic nitrogen atom and resulted in piperidinium salt; heating of the latter with the excess of Me₂SO₄ afforded doubly charged bis-methoxysulfonate. Starting from 4-methoxytetrahydropyridinium salts, meso-methoxythiapentacarbocyanine dyes were synthesized.     

Di- and Trinuclear σ-Aryl Iron and Manganese Complexes

Reactions of p- and m-diiodobenzenes, p,p'-diiodobiphenyl, and 1,3,5-triiodobenzene with anions derived from dicarbonyl(cyclopentadienyl)iron and pentacarbonylmanganese, catalyzed by palladium complexes, provide a successful route to mono-, di-, and trinuclear -aryl iron and manganese complexes.     

Syntheses of Conjugated Polymers for Photonics

Summary: By the Suzuki coupling reaction of 9,9-dioctyl-2,7-bis(1,3,2-dioxaborinan-2-yl)fluorene ( I ) and 3,5-di-tert-butylphenyl 2,5-dibromobenzenesulfonate ( II ) the alternating poly{[9,9-dioctylfluoren-2,7-diyl]-alt-[2-(3,5-di-tert-butyl-phenoxysulfonyl)-1,4-phenylene]} ( III ) was synthesized. Alkaline hydrolysis of III gave a conjugated polyelectrolyte carrying sulfonic acid groups ( IV ). Monomers 2,5-dibromo-3-[2-(pyren-1-yl)vinyl]thiophene and 2,5-dibromo-3-[2-(quinolin-4-yl)vinyl)thiophene were prepared and copolymerized with I to afford poly{[9,9-dioctylfluoren-2,7-diyl]-alt-[3-(2-(pyren-1-yl)vinyl)thiophen-2,5-diyl]} ( V ) and poly{[9,9-dioctylfluoren-2,7-diyl]-alt-[3-(2-(quinolin-4-yl)-vinyl)thiophen-2,5-diyl] ( VI ), respectively. Conjugated backbone of V contains the conjugated pyrene unit in the side chain. Similarly the side chain of VI contains the conjugated quinoline structure unit which can be for instance protonated. By the Suzuki polycondensation reaction of I and of the prepared methyl 3-(2,7-dibromocarbazole-9-yl)propionate ( VII ) the new poly{[9,9-dioctylfluorene-2,7-diyl]-alt-[9-(2-methoxycarbonylethyl)carbazole-2,7-diyl]} ( VIII ) was synthesized and characterized.     

Synthesis and comparison of the structure–property relationships of symmetric and asymmetric water‐soluble poly(p‐phenylene)s

Sodium salts of water‐soluble polymers poly{[2,5‐bis(3‐sulfonatopropoxy)‐1,4‐phenylene]‐alt‐[2,5‐bis(hexyloxy)‐1,4‐phenylene]} ( P1 ), poly{[2,5‐bis(3‐sulfonatopropoxy)‐1,4‐phenylene]‐alt‐[2,5‐bis(dodecyloxy)‐1,4‐phenylene]} ( P2 ), poly{[2,5‐bis(3‐sulfonatopropoxy)‐1,4‐phenylene]‐alt‐[2,5‐bis(dibenzyloxy)‐1,4‐phenylene]} ( P3 ), poly[2‐hexyloxy‐5‐(3‐sulfonatopropoxy)‐1,4‐phenylene] ( P4 ), and poly[2‐dodecyloxy‐5‐(3‐sulfonatopropoxy)‐1,4‐phenylene] ( P5 )] were synthesized with Suzuki coupling reactions and fully characterized. The first group of polymers ( P1 – P3 ) with symmetric structures gave lower absorption maxima [maximum absorption wavelength (λ_max) = 296–305 nm] and emission maxima [maximum emission wavelength (λ_em) = 361–398 nm] than asymmetric polymers P4 (λ_max = 329 nm, λ_em = 399 nm) and P5 (λ_max = 335 nm, λ_em = 401 nm). The aggregation properties of polymers P1 – P5 in different solvent mixtures were investigated, and their influence on the optical properties was examined in detail. Dynamic light scattering studies of the aggregation behavior of polymer P1 in solvents indicated the presence of aggregated species of various sizes ranging from 80 to 800 nm. The presence of alkoxy groups and 3‐sulfonatopropoxy groups on adjacent phenylene rings along the polymer backbone of the first set hindered the optimization of nonpolar interactions. The alkyl chain crystallization on one side of the polymer chain and the polar interactions on the other side allowed the polymers ( P4 and P5 ) to form a lamellar structure in the polymer lattice. Significant quenching of the polymer fluorescence upon the addition of positively charged viologen derivatives or cytochrome‐C was also observed. The quenching effect on the polymer fluorescence confirmed that the newly synthesized polymers could be used in the fabrication of biological and chemical sensors. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3763–3777, 2006     

Synthesis of [2-(vinyloxy)ethyl]uracil and [2-(allyloxy)ethyl]uracil

A synthesis is reported for N¹-mono- and N¹,N³-disubstituted uracil derivatives containing a terminal carbon-carbon double bond in the side-chain. Alkylation of vinyl 2-chloroethyl ether by uracil potassium salts leads to a mixture of 1-[2-(vinyloxy)ethyl] and 1,3-di[2-(vinyloxy)ethyl] derivatives while treatment of 2,4-bis(trimethylsilyloxy)pyrimidines by vinyl 2-chloroethyl ether leads exclusively to N¹-monosubstituted products. Alkylation of cytosine by this chloroether gave 1-[2-(vinyloxy)ethyl]cytosine. The synthesis of 1-[2-(allyloxy)ethyl]uracil derivatives was carried out by treatment of uracil potassium salts by 1-(allyloxy)-2-(p-toluenesulfonyloxy)ethane.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 393–397, March, 1993.     

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.     

基于2,5-二(4′-甲酰基苯基)苯乙烯的螺旋链光学活性聚合物的合成与表征

通过2,5-二溴苯乙烯与对甲酰基苯硼酸的Suzuki偶联反应得到2,5-二(4′-甲酰基苯基)苯乙烯.在催化剂量的冰乙酸存在下,与光学纯的(S)-(-)-α-甲基苄胺或(R)-(+)-α-甲基苄胺发生缩和反应,得到了一对手性非外消旋单体,(+)-2,5-二{4-′[(N-(S)-α-甲基苄亚胺基)次甲基]苯基}苯乙烯和(-)-2,5-二{4′-[(N-(R)-α-甲基苄亚胺基)次甲基]苯基}苯乙烯.以偶氮二异丁腈(AIBN)或过氧化苯甲酰(BPO)为引发剂,经自由基溶液聚合得到光学活性聚合物.比旋光度、紫外-可见吸收光谱以及圆二色光谱研究表明,聚合物主链可能形成了某一方向占优的稳定螺旋构象,且该螺旋构象的旋光方向与单体的旋光方向相反.聚合条件对聚合物的光学活性有很大影响,在极性较大的芳香族溶剂和较高温度下得到的聚合物具有和单体相差更大的比旋光度.侧基的手性基团脱除后,聚合物仍具有一定的旋光性,说明聚合过程中形成的螺旋手性具有一定的记忆效应.     

Polyaromatic pyrazines: Synthesis and thermogravimetric analysis

The syntheses of five polyaromatic pyrazine polymers are described. These polymers were synthesized by the condensation of bis-α-haloaromatic ketones with ammonia in N,N-dimethylacetamide (DMAc) solvent in the presence of air or peroxides. The condensation of bis-p-(α-bromoacetyl)benzene (IIIa), bis-p,p′-(α-chloroacetyl)biphenyl (IIIb) bis-p,p′-(α-chloroacetyl)diphenyl ether (IIIc), bis-p,p′-(α-chloroacetyl)diphenylmethane (IIId), and α,α′-dibenzoyl-α,α′-dibromo-p-xylene (V) under these reaction conditions gave poly[2,5-(1,4-phenylene)pyrazine] (IVa), poly[2,5-(4,4′-biphenylene)-pyrazine] (IVb), poly[2,5-(4,4′-oxydiphenylene)pyrazine] (IVc), poly[2,5-(4,4′-methylenediphenylene)pyrazine] (IVd), and poly[2,5-(1,4-phenylene)-3,6-diphenylpyrazine] (VI), respectively. Thermogravimetric analysis (TGA) of these polymers showed them to be thermally stable up to the temperature range of 450–550°C in air for short periods of time. The inherent viscosities of these polymers ranged from 0.18 to 1.30.     

Thermally stable silarylene-1,3,4-oxadiazole polymers

The effects of incorporating a p-phenylene- (or m-phenylene)-1,3,4-oxadiazole fragment into the backbone of poly[1,4-phenylene(diphenylsilyl)-1,4-phenylene-2,5-(1,3,4-oxadiazole)], which was developed by the authors, was investigated. Bis[(p-carbohydrazidophenyl)]diphenylsilane was copolymerized with dipentachlorophenyl terephthalate or isophthalate to produce the prepolymers poly[N-(p-diphenylsilylbenzoyl)-N′N″-(terephthaloyl)-N″′-(p-benzoyl)dihydrazide] and poly[N-(p-diphenylsilylbenzoyl)-N′,-N″-(isophthaloyl)-N″′-p-(benzoyl) dihydrazide], respectively. The polyhydrazides were converted by thermal dehydration into poly[1,4-phenylene(diphenylsilyl)-1,4-phenylene-(1,3,4-oxadiazole-2,5-diyl)-1,4-phenylene-2,5-(1,3,4-oxadiazole)] and poly[1,4-phenyl-ene(diphenylsilyl)-1,4-phenylene-(1,3,4-oxadiazole-2,5-diyl)-1,3,4-(oxadiazole)]. The new polymers were soluble in organic solvents. Films cast from these solutions exhibited good adhesion to glass and metal surfaces. Thermal analysis showed that the heat stability of all these polymers was about the same and that they were resistant to decomposition when heated in air to about 400°C. The results also indicated that these polymers were somewhat less heat-resistant than samples of poly-[1,4-phenylene(diphenylsilyl)-1,4-phenylene-2,5-]1,3,4-(oxadiazole) synthesized from bis(p-carbohydrazidophenyl)diphenylsilane and bis-(p-carbopentachlorophenoxy-phenyl)diphenylsilane.     

新型亲水性共轭聚合物的制备及光催化制氢性能

制备了聚({4,8-双[(2,5,8,11,14,17,20-七氧二十二烷-22-基)氧基]苯并[1,2-b∶4,5-b']二噻吩}-交替-[2,5-二(噻唑-2-基)吡嗪])(P7O-2N-2N)和聚({4,8-双[(2,5,8,11,14,17,20-七氧二十二烷-22-基)氧基]苯并[1,2-b∶4,5-b']二噻吩}-交替-[3,6-双(5-溴-2-噻吩基)-1,2,4,5-四嗪])(P7O-4N)2个亲水性共轭聚合物, 通过调节主链含氮杂环上氮原子的位置, 系统研究了主链结构对材料吸收光谱、 能级、 氢结合自由能及光催化性能的影响. 研究发现, 与P7O-2N-2N相比, P7O-4N表现出更强的链间聚集、 更低的氢结合自由能及更好的光催化制氢性能.     

Preparation of polymeric alcohol bearing oligo(oxyethylene) moiety by radical polyaddition through ketyl radical

Hydrophilic polymers having both oligo(oxyethylene) moieties and tertiary alcohol units in the main chain were prepared by the radical polyaddition of the dike-tones with distyryl compounds by using samarium(II) iodide as an electron transfer agent. Polyaddition of 4,4′-(1,4-phenylene)bis-2-butanone or 6,9-dioxatetradeca-2,13-dione with distyryl compounds such as 1,15-di(4-ethenylphenyl)-2,5,8,11,14-pentaoxapentadecane, 1,18-di(4-ethenylphenyl)-2,5,8,11,14,17-hexaoxaoctadecane, or 1,21-di(4-ethenylphenyl)-2,5,8,11,14,17,20-heptaoxaheneicosane resulted in the formation of the corresponding polymeric alcohols in moderate yields (46–75%). The produced polymers showed high solubility in common solvents, and their molecular weights estimated by GPC (THF, polystyrene standard) were 5200–8100. No serious difference in the molecular weight of the polymer between after and before the treatment with cerium ammonium nitrate indicated that the produced polymers were inert under the oxidative condition where oxidative cleavage of the main chain of poly(vinyl alcohol) takes place. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 715–720, 1997     

Synthesis and properties of dipyridinium betaines of derivatives of 1,4-benzoquinone and tetracyanoquinodimethane

Reaction of chloranil with excess pyridine gives the poorly stable 2,5-di(N-pyridinium)-3,6-dichloro-1,4-benzoquinone dichloride which is readily hydrolyzed to give the bisbetaine of 2,5-di(N-pyridinium)-1,4-benzoquinone-3,6-dioxide. Treatment with acid gives its mono- and bisprotonated derivatives as the perchlorate and dibromide and bromination gives the betaine 2-bromo-2,5-di(N-pyridinium)-5-cyclohexene-1,3,4-trione-6-oxide perbromide. The reaction of malonodinitrile with 2,5-di(N-pyridinium)-3,6-dichloro-1,4-benzoquinone dichloride in situ gives the poorly stable bisbetaine of 2,5-di(N-pyridinium)-7,7,8,8-tetracyanoquinodimethane-3,6-dioxide.Riga Technical University, Riga LV-1048. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 346–349, March, 1998.