高效液相色谱法测定3,4-二氟苯腈和3,4-二氯苯腈

3,4-二氟苯腈是一种重要的中间体,目前合成方法有采用3,4-二氯苯腈为原料,通相转移催化制备,由此建立了反应过程中同时测定3,4-二氟苯腈和3,4-二氯苯腈的高效液相色谱定量分析方法。以C18色谱柱为分离柱,70%甲醇水溶液为流动相;紫外检测波长设定为210 nm,可以实现反应液中这两种物质的同时检测。3,4-二氟苯腈和3,4-二氯苯腈的最低检出浓度分别为0.04和0.03μg/m L,线性范围分别为0.1~500和0.1~100μg/m L,方法的回收率为92%~106%,相对标准偏差(RSD)为1.0%~2.5%。此外,进一步考察C18 SPE小柱富集微量3,4-二氯苯腈的方法,可以实现3,4-二氟苯腈粗品中3,4-二氯苯腈的含量分析,自制的3,4-二氟苯腈样品中,3,4-二氯苯腈的含量为0.2%,加标回收率为97%。     

3,4-二氟苯腈的合成技术进展及应用

3,4-二氟苯腈是制备除草剂氰氟草酯的重要中间体.介绍了3,4-二氟苯腈的7种合成方法,即3,4-二氯苯腈直接氟化路线、3,4-二氟甲苯路线、3,4-二氟苯甲酸脱水路线、1-溴-3,4-二氟苯路线、4-氯苯腈路线、3,4-二氟硝基苯重氮化路线和3,4-二硝基甲苯路线.对各种方法在农药生产上的应用和市场前景做了简单的分析,并对3,4-二氯苯腈催化直接氟化法做了重点评述,是一条易于实现工业化的合适路线.     

相转移催化合成3,4-二氟苯腈的研究

以3,4-二氯苯腈为原料,采用相转移催化合成了3,4-二氟苯腈。考察了不同相转移催化剂、物质的量比、温度、水对反应的影响。结果表明,双-(N-双(二甲胺基)亚甲基)-氯化亚铵盐为最优催化剂,反应体系水含量控制在0.05%以下,在投料比为n(3,4-二氯苯腈)∶n(KF)∶n(催化剂)=1∶3∶0.1,140℃反应3h,190℃反应5h,3,4-二氯苯腈转化率为99%,产物3,4-二氟苯腈的收率为81%,纯度为99%。相比于先前的报道,本工艺使用新颖的N-烷基共轭季铵盐催化剂,采用分段升温法,明显降低了反应温度,缩短了反应时间,有效减少了脱卤、聚合、焦化等副反应的产生,进一步提高了3,4-二氟苯腈的收率。     

硝基直接氟化法合成3,4-二氟苯腈

以3-硝基-4-氟苯腈为原料,以四甲基氟化铵为氟化剂合成了3,4-二氟苯腈.研究表明:最适宜的反应温度区域为120～140℃,最佳溶剂为二甲基亚砜,使用催化剂18-冠-6-醚能提高转化率,达86.7%.     

3，4-二氟苯腈的合成技术进展

3,4-二氟苯腈是制备除草剂氰氟草酯的重要中间体,该除草剂高效、低毒、低残留,对稻类作物非常安全并具有优良的选择性,可防除禾本科杂草,对稗草、千金子、看麦娘、小糠草等具有良好的效果。如何利用廉价的原料和最简单的工艺来合成3,4-二氟苯腈,进而合成出高效价廉氰氟草酯,是该农药能否在我国大面积推广应用的关键。     

除草剂氰氟草酯的合成

对苯二酚和3,4-二氟苯腈通过选择性单醚化反应合成中间体4-(4-氰基-2-氟苯氧基)苯酚,再与(S)-2-(4-甲基苯磺酰氧基)丙酸丁酯反应得到氰氟草酯,所得产物经过MS和1H NMR确证.在较佳的反应条件下,反应总收率为82.2%,氰氟草酯的化学纯度为98.6%,ee值为98.0%.     

2，6—二氟苯腈的合成及其在农药合成中的应用

简要综述了2,6-二氟苯腈的合成方法及其在农药合成中的应用,探讨了各种合成路线的优缺点。由2,6-二氟苯腈衍生的2,6-二氟苯甲酰胺等化合物是合成苯甲酰脲类杀虫杀螨剂和除草剂的重要原料。这是一种具有广阔市场发展前景精细化工中间体。     

一步法合成3,4-二氟苯腈

以3,4-二氟溴苯与氰化亚铜为原料,一步合成3,4-二氟苯腈,较佳的合成条件为:氰化亚铜和3,4-二氟溴苯的摩尔比为1.3∶1,反应温度150℃,反应时间10 h,溶剂为N,N-二甲基甲酰胺,收率81.2%,产品含量99.1%。通过元素分析、红外光谱、核磁共振、质谱分析对目标产物进行了结构鉴定。该法具有选择性强、纯度高、反应步骤少以及收率理想的优势,是一条适合大规模工业化生产的路线。     

盐酸埃罗替尼中间体3,4-二(2-甲氧基乙氧基)苯腈 合成新工艺研究

盐酸埃罗替尼是第一个应用于临床的口服表皮生长因子受体(EGFR)抑制剂,其中3,4-二(2-甲氧基乙氧基)苯腈是盐酸埃罗替尼合成的关键中间体。以儿茶酚为原料,经醚化、Vilsmeier反应、氰基化3步反应合成了3,4-二(2-甲氧基乙氧基)苯腈,总收率达61.2%,产品结构经NMR和MS确证。该工艺原料价廉易得、操作简便、成本较低、收率较高,适合工业化生产。     

3,4-二羟基苯腈的合成

以3-甲氧基-4-羟基苯甲醛（香兰素）为原料,经与盐酸羟胺反应得到3甲氧基-4-羟基苯腈,再与碱金属卤化物经脱甲基化反应合成3,4-二羟基苯腈,产品含量99.8%,以香兰素计总收率75.2%。与其他合成方法比较,这条合成路线更适合于工业化。     

3,4-Dichlorophenoxyacetate interleaved into anionic clay for controlled release formulation of a new environmentally friendly agrochemical

A new layered organic–inorganic nanohybrid material, zinc-aluminum-3,4-dicholorophenoxyacetate (N3,4-D) in which an agrochemical, 3,4-dichlorophenoxyacetic acid (3,4-D), is intercalated into zinc-aluminum-layered double hydroxide (ZAL), was synthesized by coprecipitation method. A well-ordered nanomaterial was formed with a percentage loading of 53.5% (w/w). Due to the inclusion of 3,4-D, basal spacing expanded from 8.9 Å in ZAL to 18.7 Å in N3,4-D. The Fourier transform infrared study shows that the absorption bands of the resulting nanohybrid composed of both the 3,4-D and ZAL further confirmed the intercalation episode. Thermal analysis shows that ZAL host enhances the thermal stability of 3,4-D. Controlled-release experiment shows that the release of 3,4-D in the aqueous media is in the order of phosphate > carbonate > sulfate > chloride. These studies demonstrate the successful intercalation of the 3,4-D and its controlled release property in various aqueous media.     

In Vitro Reactivity of the Glucose Degradation Product 3,4-Dideoxyglucosone-3-ene (3,4-DGE) towards Abundant Components of the Human Blood Circulatory System

3,4-Dideoxyglucosone-3-ene (3,4-DGE) is a glucose degradation product present in processed foods and medicinal products. Additionally, its constant formation from 3-deoxyglucosone in plasma has been suggested. Due to its α,β-unsaturated dicarbonyl moiety, 3,4-DGE is highly reactive and has shown harmful effects in vitro. Here, we investigated the impact of major components of the human blood circulatory system on 3,4-DGE in vitro. Under physiological conditions, plasma concentrations of human serum albumin (HSA) reacted efficiently with 3,4-DGE, resulting in only 8.5% of the initial 3,4-DGE concentration after seven hours (vs. 83.4% without HSA, p < 0.001). Thereby, accessible thiol groups were reduced from 0.121 to 0.064 mol/mol HSA, whereas ketoprofen binding and esterase-like activity of HSA were not affected. Plasma concentrations of glutathione (GSH) reacted immediately and completely with 3,4-DGE, leading to two stereoisomeric adducts. Plasma concentrations of immunoglobulin G (IgG) bound to 3,4-DGE to a lower extent, resulting in 62.6% 3,4-DGE after seven hours (vs. 82.2% in the control, p < 0.01). Immobilized human collagen type IV did not alter 3,4-DGE concentrations. The results indicated that particularly HSA, GSH, and IgG readily scavenge 3,4-DGE after its appearance in the blood stream, which may be associated with a reduced antioxidative and cytoprotective activity for the living cells and, thus, the human organism by blocking free thiol groups.     

羟基酪醇的合成

以3,4-二甲氧基苯乙酸为起始原料,制得3,4-二羟基苯乙酸,3,4-二羟基苯乙酸再在SOCl2存在下与甲醇反应制得3,4-二羟基苯乙酸甲酯,以Bouveault-Blanc反应为基本原理,通过钠/乙醇还原3,4-二羟基苯乙酸甲酯制得羟基酪醇,并通过1HNMR、IR、MS等方法对其进行了表征。该文还对影响羟基酪醇收率的原料配比、反应时间、反应温度以及钠/乙醇还原3,4-二羟基苯乙酸甲酯反应的机理进行了研究和探讨。     

3,4-亚甲二氧苯基-2-丙酮的合成研究

以3,4-亚甲二氧基苯甲醛和硝基乙烷为原料,经Knoevenagel反应生成3,4-亚甲二氧苯基-2-硝基丙烯,再通过还原和水解反应,合成3,4-亚甲二氧苯基-2-丙酮。研究了Knoevenagel反应中催化剂的选择以及还原与水解反应中HCl与3,4-亚甲二氧苯基-2-硝基丙烯的摩尔比对产率的影响。结果表明,较优反应条件为:Knoevenagel反应采用醋酸铵作催化剂,冰醋酸作溶剂,回流3 h,产率可达81.2%;还原与水解反应中,HCl与3,4-亚甲二氧苯基-2-硝基丙烯的摩尔比为2.72∶1时,产率为66.3%。     

Synthesis and Changes of Conductivities and Thermal Stabilities of 4,4′-Oxybis [N-(3,4-Dihydroxybenzilidene) Aniline] Chelate Polymers

In this study novel metal coordination polymers were synthesized such as poly-4,4′-oxybis[N-(3,4-dihydroxybenzilidene)aniline] (P-3,4-HBA) containing Cu, Co, Pb, Ni, Zn, Cd, Cr, Mn and Zr metals in the polymer backbone. The polymers are abbreviated as P-3,4-HBA-Cu, P-3,4-HBA-Co, P-3,4-HBA-Pb, P-3,4-HBA-Ni, P-3,4-HBA-Zn, P-3,4-HBA-Cd, P-3,4-HBA-Cr, P-3,4-HBA-Mn and P-3,4-HBA-Zr, respectively. To confirm the structures FT-IR, UV-vis, ¹H and ¹³C-NMR spectral techniques were used. Additional characterization of the polymers was made by size exclusion chromatography (SEC), TGA-DTA and solubility tests. By TGA analysis, P-3,4-HBA-Zr was the most stable polymer against thermal degradation among those synthesized. In addition, it was found that, with exception of P-3,4-HBA-Cr, the other synthesized polymers have little solubility in many organic solvents and water. According to SEC results, P-3,4-HBA-Cr has a single fraction containing 21–22 mer units. Electrical conductivities of the monomer and polymers were measured by the four-point probe technique. The polymers were semiconductors; and, some of their conductivities can be increased via doping with iodine. According to the electrical conductivities of the undoped P-3,4-HBA-Cr and P-3,4-HBA-Zr polymers have nearly ten-times higher conductivities in comparison to the others. From UV-vis measurements, the optical band gaps (E _g ) of 3,4-HBA and P-3,4-HBA-Cr were 2.58 and 2.39 eV, respectively. This result indicates that P-3,4-HBA-Cr has a lower band gap and consequently higher electrical conductivity than 3,4-HBA. Thus, with good solubility, high electrical conductivity and high thermal stability P-3,4-HBA-Cr may be considered as the most useful metal coordination polymer among those synthesized.     

导电聚合物单体3，4-乙烯二氧噻吩的合成

以硫代二甘酸为起始原料,经过五步反应得到产物3,4-乙烯二氧噻吩（EDOT）,过程如下：首先在浓硫酸催化条件下,硫代二甘酸与甲醇酯化生成硫代二甘酸二甲酯,产率为93．2％;产物进而与草酸二乙酯反应后得到3,4-二羟基噻吩-2,5-二甲酸二甲酯,产率为92．0％;然后经O-烷基化反应,反应中加入四丁基溴化铵作为相转移催化剂,得到3,4-乙烯二氧噻吩-2,5-二羧酸二甲酯,再经水解得到3,4-乙烯二氧噻吩-2,5-二甲酸;在DMSO为溶剂、氮气保护条件下,3,4-乙烯二氧噻吩-2,5-二甲酸在碱式碳酸铜催化作用下脱去两分子C02得到终产物EDOT。本方法中间产物及终产物的结构经由IR证实,并经过GC含量分析,总收率为34．6％。     

Study on the poly(3‐hydroxybutyrate‐co−4‐hydroxybutyrate)‐based composites toughened by synthesized polyester polyurethane elastomer

In this study, polycaprolactone(PCL)‐based polyurethane (PU) elastomer containing 45 wt % hard segment component was synthesized and characterized by fourier transform infrared spectroscopy, gel permeation chromatography, and X‐ray diffraction. As a toughening agent, the as‐synthesized PU was incorporated into biodegradable poly(3‐hydroxybutyrate‐co‐4‐hydroxybutyrate) [P(3,4)HB] by solution casting to prepare P(3,4)HB/PU composites. The microstructure and properties of P(3,4)HB/PU composites were investigated using transmission electron microscopy, X‐ray diffraction, tensile testing, scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, and activated sludge degradation testing. The results show that PU can disperse well in a P(3,4)HB matrix. The elongation at break of P(3,4)HB/PU composites is remarkably increased while the yield strength and elastic modulus are decreased with an increase in PU content. At the same time, it is found that the fracture characteristic of P(3,4)HB is obviously transformed from brittleness into ductility with a gradual increase in PU loading. Moreover, the thermal stability of P(3,4)HB/PU composites is significantly improved compared with that of pure P(3,4)HB. In addition, the biodegradation rate of P(3,4)HB/PU composites is evidently reduced with the increase of PU content in the activated sludge degradation testing. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42740.     

催化加氢制备3,4-亚甲二氧基苯胺

3,4 亚甲二氧基硝基苯在95%乙醇溶剂中用雷尼镍催化加氢制备了3,4 亚甲二氧基苯胺。对催化剂用量和活性稳定性进行了研究,讨论了溶剂用量、温度、压力等因素对加氢反应的影响。结果表明最佳工艺参数为:雷尼镍∶乙醇∶3,4 亚甲二氧基硝基苯=0.15∶6∶1(质量比),反应温度40℃,氢压0.45～0.50MPa,搅拌速度450r/min,反应至不再吸氢为止,产品收率在97%以上,纯度为98%。     

COMPARATIVE METABOLISM OF PHENANTHRO[3,4-B]THIOPHENE,PHENANTHRO[4,3-B]THIOPHENE AND THEIR CARBON ANALOG BENZO[C]PHENANTHRENE BY RAT LIVER MICROSOMES

Phenanthro[3,4-b]thiophene (P[3,4-b]T) and phenanthro[4,3-b]thiophene (P[4,3-b]T) are thiasters of weakly mutagenic benzo[c]phenanthrene (B[c]P). These polycyclic sulfur heterocycles (thia-PAHs) represent a group of chemicals which have been identified in cigarette smoke. P[3,4-b]T is a potent mutagen in Salmonella typhimurium strain TA100 in the presence of rat liver S9, whereas its isosteric isomer P[4,3-b]T is a nonmutagenic compound. In order to understand the mechanism underlying the differences in the mutagenic activity of P[3,4-b]T and P[4,3-b]T, we have investigated the metabolism of P[3,4-b]T, P[4,3-b]T, and their carbon analogue B[c]P by rat liver microsomes. The liver microsomes from rats treated with Aroclor 1254 metabolized P[3,4-b]T, P[3,4-b]T, and B[c]P at a rate nearly 7- to 9-fold greater than of the control liver microsomes. High-performance liquid chromatography (HPLC) analysis of the metabolites formed showed that B[c]P was metabolized almost exclusively to its dihydrodiols which comprised predominantly K-region diol as noted in the previous studies. Our preliminary studies on the metabolism of P[3,4-b]T, P[4,3-b]T and B[c]P by liver microsomes from control and Aroclor 1254-treated rats have shown a significant reduction in the formation of 6,7-diol (K-region diol) and 8,9-diol (diol with a bay-region double bond) of the two thia-PAHs compared to the formation of analogous 5,6-diol (K-region diol) and 3,4-diol (diol with a bay-region double bond) from B[c]P. Both P[3,4-b]T and P[4,3b]T produced a major, relatively nonpolar metabolite(s) (80–96% of total metabolites). These studies indicate that the highly mutagenic P[3,4-b]T is not metabolized to dihydrodiol with a bay-region double bond to any greater extent than the weakly or nonmutagenic B[c]P or P[4,3-b]T, suggesting that the metabolite(s) other than P[3,4-b]T8,9-diol is likely to be involved in the mutagenicity of P[3,4-b]T.