Synthesis of difuran diesters from furfural,and their evaluation as plasticizers for polyvinyl chloride

The compounds 1,1-bis[5-(2-ethylhexyl, 2-octyl, hexyl, and butyl)carboxylate-2-furyl)ethane, and 5,5′-dihexylcarboxylate-2,2′ bifuran were synthesized from furfural and characterized for their plasticizing abilities toward polyvinyl chloride (PVC) by dynamic mechanical thermal analyses (DMTA) with di-(2-ethylhexyl)phthalate (DOP)as the standard of reference. DMTA gave values for the depression of the glass-transition temperature (T_g) per mass fraction of plasticizer, and it also yielded a set of parameters, relative to those of DOP, which describe the compatability of the furan diesters with PVC. These values are compared to those of DOP and furan diesters incorporating only one furan ring in the molecular structure, which have previously been tested by this method. The difuran plasticizers are less efficient in lowering T_g than the monofuran plasticizers or DOP, with 1,1-bis[5-(2-octyl)carboxylate-2-furyl]ethane the least efficient and 1,1-bis(5-hexylcarboxylate-2-furyl)ethane the most efficient. On average the compatability toward PVC is better than that of DOP, and similar to that of analogous monofuran structures. © 1995 John Wiley & Sons, Inc.     

Investigation of short-term stability in high efficiency polymer : nonfullerene solar cells via quick current-voltage cycling method

The short-term stability of high efficiency polymer: nonfullerene solar cells was investigated by employing a quick (ten cycles) current density-voltage (J-V) cycling method. Polymer: nonfullerene solar cells with initial power conversion efficiency (PCE) of >10% were fabricated using bulk heterojunction (BHJ) films of poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2-b:4,5b′]dithiophene))-alt-(5,5-(1′,3′-di-2-thienyl-5,7′-bis(2-ethylhexyl)benzo[1′,2′-c:4′,5′-c′]dithiophene-4,8-dione))] (PBDB-T) and 3,9-bis(2-methylene-((3-(1,1-dicyanomethylene)-6/7-methyl)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]dithiophene (IT-M). One set of the BHJ (PBDB-T: IT-M) films was thermally annealed at 160 oC for 30min, while another set was used without any thermal treatment after spin-coating. The quick J-V scan (cycling) measurement disclosed that the PCE decay was relatively slower for the annealed BHJ layers than the unannealed (as-cast) BHJ layers. As a result, after ten cycles, the annealed BHJ layers delivered higher PCE than the unannealed BHJ layers due to higher and more stable trend in fill factor. The present quick J-V cycling method is simple but expected to be useful for the prediction of short-term stability in organic solar cells.     

Synthesis and evaluation of dialkyl furan-2,5-dicarboxylates as plasticizers for PVC

Di(2-ethylhexyl), di(2-octyl), dihexyl, and dibutyl furan-2,5-dicarboxylate were synthesized from furfural and characterized for their plasticizing abilities toward PVC by dynamic mechanical thermal analysis (DMTA) with di(2-ethylhexyl) phthalate (DOP) as the standard of reference. DMTA gave values for the depression of the glass transition temperature (T_g) per mass fraction of plasticizer, and it also yielded a set of parameters, relative to those for DOP, which describe the compatibility of the furan diesters with PVC. The efficiency in lowering T_g as exhibited by di(2-ethylhexyl) furan-2,5-dicarboxylate is similar to that of its benzenoid analog, DOP, and was determined at 2.41 and 2.45°C per mass % plasticizer, respectively. All four furan diesters were found to be more compatible toward PVC than toward DOP, with dibutyl furan-2,5-dicarboxylate the most highly compatible. © 1994 John Wiley & Sons, Inc.     

固体超强酸SO42-/TiO2催化合成癸二酸二异辛酯

以固体超强酸SO2 -4 TiO2 为催化剂 ,癸二酸和 2 -乙基己醇为原料合成癸二酸二异辛酯 ,考察了影响反应的因素 ,结果表明最适宜的反应条件为 :醇酸物质的量比为 3.5∶1;催化剂用量为 4 .0g mol癸二酸 ;带水剂苯为 10mL ;反应时间为 4h ,酯化率达 98.2 %。     

新型过氧化物引发剂引发氯乙烯悬浮聚合动力学

研究了新型过氧化物引发剂过氧化新癸酸 1,1 二甲基-3-羟基丁基酯(Lup 610)在51.3与56.8℃以及过氧化新庚酸叔丁酯(Lup 701)和过氧化新戊酸叔己酯(HPV)在61.8℃单一引发剂引发氯乙烯悬浮聚合动力学，并采用模型计算结果绘制转化率 时间曲线，取与实验数据符合最好的f值作为引发剂的引发效率，求得引发剂Lup 610在51.3与56.8℃的引发效率分别为0.80与0.75，引发剂Lup 701和HPV在61.8℃下的引发效率分别为0.55和0.50。研究了上述引发剂与过氧化二碳酸二(2-乙基己酯)、过氧化新癸酸叔丁酯在各温度下复合引发剂引发氯乙烯悬浮聚合的动力学，与模型值相比较，发现两者能很好吻合。     

DNA cleavage activities and mechanism of a novel heterodinuclear macrocyclic complex

A new unsymmetrical bis-furan pendant-armed macrocyclic heterodinuclear Cu(II)Zn(II) complex, [CuZnL(OAc)](ClO₄)·3MeCN·H₂O(1) (H₂L was derived from the condensation between 1,6-bis(2-furyl)-2,5-bis(2-hydroxy-3-formyl-5-bromobenzyl)-2, 5-diazahexane and 1,3-diaminopropane), has been synthesized and characterized by EDS (energy dispersive spectroscopy) and X-ray crystallography determination. The interaction between the complex and calf thymus (CT) DNA was investigated by UV–vis absorption, viscosity experiment, fluorescent and CD spectroscopy. The mechanism of the cleavage of supercoiled DNA (pBR 322DNA) process was also studied. It is proposed that DNA cleavage promoted by the complex occurrence via oxidative mechanism.     

Tolyl-Substituted Siloles: Synthesis, Substituent Effects, and Aggregation-Induced Emission

The syntheses, spectroscopic characteristics, and electrochemical behavior of 1,1-dimethyl-2,5-diphenyl-3,4-bis(p-methylphenyl)silole and 1,1-dimethyl-2,3,4,5-tetra(p-methylphenyl)silole are reported. The compounds are weakly luminescent in dilute fluid solution but exhibit dramatic aggregation-induced emission (AIE). Absorbance, luminescence, and voltammetric characteristics are compared to 1,1-dimethyl-2,3,4,5-tetraphenylsilole and 1,1-dimethyl-3,4-diphenyl-2,5-bis(p-methylphenyl)silole, allowing a comparison of the effects of the position of the substituents on the silole ring. In addition, HOMO and LUMO energies and band gaps, derived from electrochemical, spectroscopic, and computational data, are reported. Substitution of the weakly electron-donating p-methyl groups on the peripheral aryl groups at the 2- and 5-positions of the silole ring results in slight red shifts in absorption and emission maxima, slight enhancement of luminescence quantum yields, slightly longer luminescence lifetimes, and more anodic oxidation potentials.     

Highly optical transparency and thermally stable polyimides containing pyridine and phenyl pendant

In order to obtain highly optical transparency polyimides, two novel aromatic diamine monomers containing pyridine and kinky structures, 1,1-bis[4-(5-amino-2-pyridinoxy)phenyl]diphenylmethane (BAPDBP) and 1,1-bis[4-(5-amino-2-pyridinoxy)phenyl]-1-phenylethane (BAPDAP), were designed and synthesized. Polyimides based on BAPDBP, BAPDAP, 2,2-bis[4-(5-amino-2-pyridinoxy)phenyl]propane (BAPDP) with various commercial dianhydrides were prepared for comparison and structure-property relationships study. The structures of the polyimides were characterized by Fourier transform infrared (FT-IR) spectrometer, wide-angle X-ray diffractograms (XRD) and elemental analysis. Film properties including solubility, optical transparency, water uptake, thermal and mechanical properties were also evaluated. The introduction of pyridine and kinky structure into the backbones that polyimides presented good optical properties with 91–97% transparent at 500 nm and a low cut-off wavelength at 353–398 nm. Moreover, phenyl pendant groups of the polyimides showed high glass transition temperatures (T_g) in the range of 257–281 °C. These results suggest that the incorporating pyridine, kinky and bulky substituents to polymer backbone can improve the optical transparency effectively without sacrificing the thermal properties.     

The effect of chemical structure of derivatives of 1,1-bis(4-hydroxyphenyl)-2,2-propane on the antiplasticization of polycarbonate

The antiplasticizing effect of ester derivatives of bisphenol A: 1,1-bis(4-hydroxyphenyl)-2,2-propane diacetate (DAPP), 1,1-bis(4-hydroxy-3,5-dichlorophenyl)-2,2-propane diacetate (DACPP), 1,1-bis(4-hydroxy-3,5-dibromophenyl)-2,2-propane diacetate (DABPP), 1,1-bis(4-hydroxy-3,5-dichlorophenyl)-2,2-propane dibenzoate (DBCPP), 1,1-bis(4-hydroxy-3,5-dichlorophenyl)-2,2-propane di-2,4-dichlorobenzoate (DCBCPP) on polycarbonate was investigated. Obtained results indicate that antiplasticizing abilities of these compounds depend on the number of polar groups in the molecule, as well as on the possibility of tight filling the free volume by the molecules in polymer–antiplasticizer system.     

Epoxidation of alkyl esters of 12,13-epoxyoleic acids and evaluation of the diepoxides as plasticizers for poly(vinyl chloride)

Methyl, propyl, butyl, isobutyl, hexyl, cyclohexyl, octyl and 2-ethylhexyl esters of 9,10:12,13-diepoxystearic acid were prepared by peracetic acid oxidation of the corresponding esters of 12,13-epoxyoleic acid. Using a 60 mole per cent excess of peracid at 30 C in chloroform as solvent, epoxidation was complete in 5 hr. A small aqueous phase was observed in the reaction mixture which decreases the amount of peracid available for reaction. This is due to the water and H₂O₂ present in the commercial peracetic acid used. Thin-layer and gas chromatographic analysis showed that the diepoxides formed as isomers. These did not react quantitatively with HBr by the Durbetaki method. Isomers of methyl and propyl diepoxy esters were separated by crystallization. The methyl (pure and mixed isomers), isobutyl, 2-ethylhexyl and octyl (all mixed isomers) diepoxy esters were evaluated as plasticizers of poly (vinyl chloride). Delta values showed that these esters have good compatibility. Results are compared with commercial epoxidized soybean oil control. These diepoxy esters show better low temperature properties and have higher migration and volatility values than the control. They are more efficient plasticizers than the control. The liquid isomer of the methyl ester, as well as the 2-ethylhexyl ester, should be useful as primary plasticizers and in combination with other plasticizers as plasticizer stabilizers. E. Utiliz. Res. Dev. Div., ARS, USDA.     

Preparation of some mixed diesters of aliphatic diols and their evaluation as plasticizers

Mixed diesters of three diols-ethylene glycol, diethylene glycol, and 2-butene-1,4-diol—were prepared wherein one of the ester moieties was benzoate. The laurates were shown to be excellent plasticizers for polyvinyl chloride (PVC) resin. Diesters containing two aroyl groups, or benzoyl and a short branched-chain alkanoyl group were also shown to be compatible plasticizers for PVC resin. Longer chain acids, including oleic and erucic, gave incompatible plasticizers. Benzoyloxyethoxyethyl laurate plasticized PVC had low temperature properties, volatility, and thermal stability superior to PVC plasticized with di-2-ethylhexyl phthalate.     

Conformational studies of polycyanurates: a study of internal stress versus molecular structure

A new parameter set (RDA-DR2.21_Inv) is shown to reproduce both the geometries and the physical and mechanical properties of three polycyanurates based on 2,2-bis(4-cyanatophenyl)propane, 1,1-bis(4-cyanatophenyl)ethane and 1,3-bis(4-cyanatophenyl-1-(1-methylethylidene))benzene. The results show a trend of internal stress within the molecule caused by varying backbone structure. The simulated Young's modulus of elasticity decreases in the order: 1,1-bis(4-cyanatophenyl)ethane>2,2-bis(4-cyanatophenyl)propane>1,3-bis(4-cyanatophenyl-1-(1-methylethylidene))benzene (from 31.11 to 14.33 GPa). Molecular dynamics simulations, carried out on 1,1-bis(4-cyanatophenyl)ethane and 1,3-bis(4-cyanatophenyl-1-(1-methylethylidene))benzene, reproduce the empirical glass transition temperatures (T_g) of the polycyanurates well, although the calculated T_g values are slightly overestimated when compared with the empirical data, presumably due to the ‘perfect’ nature of the simulated network.     

Preparation of some mono- and diesters of n,n-disubstituted amides and their evaluation as plasticizers

Mono- and diesters of fatty acid- and aromatic acid-derived N,N-disubstituted amides were prepared in which the acid moieties were alternately substituted to function as the basic amide moiety or the terminal ester moiety. Several of the esteramides were evaluated as plasticizers for polyvinyl chloride (PVC). The plasticized stocks exhibited properties that equaled, and in some instances were superior to PVC plasticized with the common plasticizer, di-2-ethylhexyl phthalate (DOP). The monoesters were more compatible than the diesters. Thermal stability was enhanced by the presence of the benzoic acid moiety in the molecule. Brittle point temperatures were shown to be a predictable characteristic for specific terminal groups, based on structural similarity of the basic molecule.     

1,1-二甲硫基-2-硝基乙烯的合成

研究了以硝基甲烷和二硫化碳为原料,合成1,1-二甲硫基-2-硝基乙烯。考察了反应温度、反应时间、甲基化试剂、溶剂、投料比等对于反应产物的影响,得到优化工艺条件为:反应温度35℃,反应时间3h。以硫酸二甲酯为甲基化试剂,常温下反应时间3 h,重结晶得1,1-二甲硫基-2-硝基乙烯,收率为84%,产物通过IR、1H-NMR鉴定。     

Diesters from Oleic Acid: Synthesis,Low Temperature Properties,and Oxidation Stability

Several diesters were prepared from commercially available oleic acid and common organic acids. The key step in the three step synthesis of oleochemical diesters entails a ring opening esterification of alkyl 9,10-epoxyoctadecanoates (alkyl: propyl, isopropyl, octyl, 2-ethylhexyl) using propionic and octanoic acids without the need for either solvent or catalyst. Each synthetic diester was evaluated for both low temperature operability and oxidation stability through measurement of cloud point, pour point, oxidation onset temperature, and signal maximum temperature. It was discovered that increasing chain length of the mid-chain ester and branching in the end-chain ester had a positive influence on the low temperature properties of diesters. Improved oxidation stability is achieved when the chain length of the mid-chain ester is decreased. Additionally, the mid-chain ester plays a larger role in oxidation stability than the end-chain ester. These products may prove useful in the search for bio-based industrial materials, such as lubricants, surfactants, and fuel additives. Product names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also be suitable.     

Asymmetric Ring-Opening Reactions of Donor-Acceptor Cyclopropanes and Cyclobutanes

Donor-acceptor (DA) cyclopropanes are particularly useful synthetic building blocks, which have been widely applied in the total synthesis of natural products and important chiral molecules in organic synthesis. The asymmetric ring-opening reactions of racemic DA cyclopropanes and cyclobutanes, for example, aryl-substituted 1,1-cyclopropane diesters and aryl-substituted 1,1-cyclobutane diesters, with nucleophiles provides versatile access to optically active γ- and δ-functionalized carbon skeletons, as well as the kinetic resolution of racemic DA cyclopropanes, which are useful chiral skeletons in organic synthesis. Recently, we have developed a series of highly enantioselective ring-opening and annulation reactions of DA cyclopropanes and cyclobutanes with various nucleophiles, such as amines, alcohols, nitrones, azomethine imines, enol silyl ethers, and indoles, by employing nickel and copper catalysts with TOX and SaBOX as ligands. The reactions worked smoothly with excellent diastereoselectivities and enantioselectivities (up to >99/1 dr and up to 99 % ee) over broad substrate scopes.     

冠醚修饰的紫精类化合物的合成与电化学性能研究

将苯并氮杂-15-冠-5的边臂链接到4,4'-联吡啶上,设计合成了3种冠醚环修饰的紫精化合物。运用紫外光谱考察了其识别碱金属离子的能力,运用循环伏安测试考察了其电化学氧化还原性质。紫外光谱测试结果显示,含有两个冠醚环的紫精化合物对金属离子有较显著的配位作用。循环伏安测试结果显示,氯化1,1'-双[2-酮-2-(苯并氮杂-15-冠-5)]-4,4'-联吡啶盐化合物具有更好的电化学信号,出现了两对可逆的氧化还原峰。     

Synthesis and characterization of polyphenylene vinylenes having <Emphasis Type="Italic">m</Emphasis>-terphenyl group: comparison of their optical properties

A series of alternate block copolymers of polyphenylene vinylenes that have 1,3-dioctyloxy phenylene in the center of kinked m-terphenyl group as one of the building blocks with either one of the aromatic groups, viz., 1,4-dioctyloxy benzene, 4,6-dioctyloxy benzene and 4,4′-dioctyloxy biphenyl, was synthesized through Heck polymerization. These alternate block copolymers, viz., poly(2,5-bis(octyloxy)phenylene vinylene alt 4′,6′-bis(octyloxy)-1,1′:3′,1″-terphenylene) (P1), poly(2,4-bis(octyloxy)phenylene vinylene alt 4′,6′-bis(octyloxy)-1,1′:3′,1″-terphenylene) (P2) and poly(4,4′-bis(octyloxy-3,3′-biphenylene vinylene alt 4′,6′-bis(octyloxy)-1,1′:3′,1″-terphenylene) (P3), were characterized for their thermal and optical properties. The synthesized polymers had good solubility in organic solvents and were stable up to 350 °C. The molecular weights of the synthesized polymers were in the range 4370–10,900 Da with polydispersity range 1.52–1.65, which were measured by the gel permeation chromatography technique. The optical properties of these polymers showed absorptions in solution at around 400, 329, and 345 nm for P1, P2, and P3 polymers, respectively. The photoluminescence emission maxima of the polymers were at around 461 nm with a shoulder 439 and 424 nm for P1, P2, and P3, respectively. Photoluminescence emission of films of these polymers showed minimum redshift (20 nm) when compared with spectra of their solutions. The optical and photoluminescence emission properties of these polymers were found to vary on the backbone structure.     

二苯基金刚烷改性3,6-咔唑共聚物的合成及性能

咔唑类蓝色发光材料固有的低玻璃化转变温度严重限制了实际应用,为了解决这个问题,本文制备了一种高稳定性聚咔唑蓝光材料。以单体3,6-二溴-9-（2-乙基己基）咔唑和N-（2-乙基己基）-3,6-二（4,4,5,5-四甲基-1,3,2-二氧硼戊烷-2-基）咔唑、1,3-二（4-溴苯基）金刚烷为原料,以四（三苯基膦）钯为催化剂,通过调整单体比例,经Suzuki反应合成了数均分子量约3500~6000的3,6-咔唑-二苯基金刚烷共聚物。差热扫描量热测试结果表明,在加入摩尔分数分别为10%、30%和50%的二苯基金刚烷后,共聚物玻璃化转变温度从3,6-咔唑均聚物的66℃分别显著升高至78℃、93℃、106℃,热重测试的失重5%热分解温度同样随着二苯基金刚烷含量的升高而升高。低含量二苯基金刚烷改性共聚物的荧光量子产率较3,6-咔唑均聚物高,显示了优良的荧光传递特性。且共聚物薄膜态时的最大荧光发射波长均处于蓝光最适波长范围内。研究结果表明：二苯基金刚烷的加入显著改善了咔唑聚合物的热稳定性能,还改善了发光性能,制备的共聚物是一种非常有应用前景的新型蓝光材料。     

Synthesis and Antimicrobial Evaluation of Some Novel Bis-α,β-Unsaturated Ketones,Nicotinonitrile, 1,2-Dihydropyridine-3-carbonitrile,Fused Thieno[2,3-b]pyridine and Pyrazolo[3,4-b]pyridine Derivatives

The title compounds were prepared by reaction of 1,1′-(5-methyl-1-phenyl-1H-pyrazole-3,4-diyl)diethanone (1) with different aromatic aldehydes 2a–c, namely Furfural (2a), 4-chlorobenzaldehyde (2b) and 4-methoxybenzaldhyde (2c) to yield the corresponding α,β-unsaturated ketones 3a–c. Compound 3 was reacted with malononitrile, 2-cyanoacetamide or 2-cyanothioacetamide yielded the corresponding bis[2-amino-6-(aryl)nicotinonitrile] 4a–c, bis[6-(2-aryl)-2-oxo-1,2-dihydropyridine-3-carbonitrile] 5a–c or bis[6-(2-aryl)-2-thioxo-1,2-dihydropyridine-3-carbonitrile] 6a,b, respectively. The reaction of compound 6a with each of 2-chloro-N-(4-bromophenyl) acetamide (7a), chloroacetamide (7b) in ethanolic sodium ethoxide solution at room temperature to give the corresponding 4,4′-(5-methyl-1-phenyl-1H-pyrazole-3,4-diyl)bis-6-(2-furyl)thieno[2,3-b]pyridine-2-carboxamide] derivatives 9a,b. While compound 6a reacted with hydrazine hydrate yielded the 4,4′-(5-methyl-1-phenyl-1H-pyrazole-3,4-diyl)bis[6-(2-furyl)-1H-pyrazolo[3,4-b]pyridin-3-amine] 11. The structures of the products were elucidated based on their spectral properties, elemental analyses and, wherever possible, by alternate synthesis. Antimicrobial evaluation of the products was carried out.