乙基香兰素的相转移催化合成

报道了应用相转移催化技术合成中间体邻乙氧基苯酚及最终产物乙基香兰素,考察了反应温度、时间、物料配比等因素对合成的影响,确定了最佳反应条件,邻乙氧基苯酚反应的最佳温度60℃;合成乙基香兰素最佳温度55～60℃。研究结果显示聚乙二醇作为相转移催化剂合成邻乙氧基苯酚,四丁基溴化胺相转移催化合成乙基香兰素,其结果均优于以往报道,邻乙氧基苯酚最高收率可达75.5%,乙基香兰素最高收率可达70%。     

相转移催化合成邻乙氧基苯酚技术研究

研究了以聚乙二醇(PEG-400)作为相转移催化剂,由邻苯二酚(C6H6O2)与溴乙烷(C2H5Br)为主要原料合成邻乙氧基苯酚(C8H10O2)工艺。以邻乙氧基苯酚的收率为考察指标,考察了反应温度、反应时间、原料物质的量比和催化剂用量(以邻苯二酚的质量为计算依据)等对反应收率的影响,通过正交实验以及单因素实验,建立PEG相转移催化条件下合成邻乙氧基苯酚的适宜工艺条件即:n(C6H6O2)∶n(NaOH)∶n(C2H5Br)=1∶1.2∶1.2,反应温度为68℃,反应时间为6 h,催化剂用量为2%;该反应条件下,产品邻乙氧基苯酚收率65%。以PEG-400为相转移催化剂合成邻乙氧基苯酚的方法工艺成本低、污染小、操作简单易行,适应于工业化生产。     

相转移催化法合成乙基香兰素的工艺改进

以邻苯二酚为原料,首先合成中间体邻乙氧基苯酚,然后以十六烷基三乙基溴化铵为相转移催化剂合成了乙基香兰素,考察了相转移催化剂的选择及反应温度,最后收率为55.2%。     

香料中间体邻乙氧基苯酚合成研究

以邻苯二酚和溴乙烷为原料,在碱性条件及单一溶剂中合成了邻乙氧基苯酚。对影响反应的各种因素进行了探讨,确定了适宜的合成条件为反应温度65℃,反应时间3.5h,反应终点的pH值控制为3。在此条件下,邻乙氧基苯酚收率为87.6%。     

邻乙氧基苯酚的合成研究

文章介绍了以邻苯二酚和溴乙烷为原料,无水乙醇为溶剂,在碱性条件中合成了邻乙氧基苯酚,并对反应中的各种影响因素进行了考察,得到较佳工艺条件为：在氮气氛保护中,物料邻苯二酚、溴乙烷与氢氧化钠的摩尔比为1：1．2：1．1,催化剂聚乙二醇1540用量为1．0g时,邻乙氧基苯酚的收率为88．7％。     

5-乙酰基-2,3-二氢苯并呋喃的合成

采用邻溴苯酚为初始原料,在相转移催化剂作用下经烷基化合成2-(2-氯乙氧基)-1-溴苯(1),通过生成格氏试剂合成2,3-二氢苯并呋喃(2),由傅-克酰基化反应合成5-乙酰基-2,3-二氢苯并呋喃(3)。反应过程以薄层色谱法监控,并通过元素分析、1HNMR对各中间体的组成和结构进行了确证和表征。     

苯酚-甲醇气相烷基化合成邻甲酚的工艺技术

邻甲酚作为一种重要的精细化工中间体,主要用于合成树脂、农药、医药、染料、抗氧剂等的合成原料。近年来,由于邻甲酚下游产品的快速增长,邻甲酚的市场需求日益增长。本文简要介绍苯酚-甲醇气相烷基化合成邻甲酚的工艺技术,该技术使工业苯酚与工业甲醇在固定列管反应器内催化剂的催化作用下,通过邻位甲基化合成邻甲酚粗产物。该反应温度为320～360℃,反应压力为常压,原料进料质量空速为0.8 hr^-1,原料配比苯酚∶甲醇∶水=94∶64∶27(质量比),催化剂再生温度为400～450℃。该反应过程中反应物苯酚的单程转化率为45%～47%,邻甲酚选择性在90%以上。之后将得到的粗产物进行五塔精馏,在优化操作条件下,可获得连续、稳定以及纯度> 99.7%的邻甲酚合格产品。     

邻乙氧基苯酚的合成与精制

对邻苯二酚、氯乙烷法合成邻乙氧基苯酚工艺进行了研究,改进了现有技术存在的不足,提高了邻乙氧基苯酚的产品纯度,并提供了一种邻乙氧基苯酚的精制方法。     

聚乙二醇催化合成邻乙氧基苯酚的研究

以邻苯二酚和溴乙烷为主要原料,以聚乙二醇-600为催化剂,在不同条件进行反应,得到产物邻乙氧基苯酚,产率可到81%。探讨了反应时间、氢氧化钠用量,邻苯二酚和溴乙烷物质的量比以及催化剂用量对反应的影响。     

2-溴乙氧基苯的相转移催化合成研究

在四丁基溴化铵相转移催化剂存在下,以苯酚、1,2-二溴乙烷为原料合成2-溴乙氧基苯,分别研究了反应温度、反应时间、原料配比、催化剂用量等条件对合成反应的影响,确定了最佳工艺条件。该方法合成2-溴乙氧基苯的最佳工艺条件是:反应温度100°C;反应时间6 h;n(苯酚)∶n(1,2-二溴乙烷)=1∶1.15;n(苯酚)∶n(氢氧化钠)=1∶1.15;溶剂用量为40 mL(相对于0.15 mol苯酚),催化剂用量为1 g(相对于0.15 mol苯酚),2-溴乙氧基苯的收率可达到88.9%以上,产品纯度98.5%。     

Chemically and enzymatically catalyzed synthesis of C6–C10 alkyl benzoates

The esterification of benzoic acid with n‐hexanol, n‐octanol, 2‐ethyl hexanol and n‐decanol was investigated in detail. An analysis of the reaction kinetics of esterification in the presence of different commercially available chemical catalysts was carried out. The effects of catalyst type and loading on the reaction rate were studied. Although the considered reaction is bimolecular, it showed a first‐order behavior, and a linear dependence with respect to the catalyst concentration was observed. Hence, a new approach is presented to describe the reaction kinetics accurately over a wide range. The application of biotechnological synthesis applying different enzymes as catalysts offers an interesting alternative besides chemical synthesis. Especially an esterase from Bacillus subtilis immobilized on Sepabeads EC‐EP showed high stability and was applied for 2 days in the synthesis of hexyl benzoate. Nevertheless, the chemical reaction route remains superior with respect to the catalyst activities under the applied conditions, which were 25 kU/g for the chemical reaction and 0.7 kU/g for the best enzymatic conversion.     

Total Synthesis of (−)‐Doliculide,Structure–Activity Relationship Studies and Its Binding to F‐Actin

Actin, an abundant protein in most eukaryotic cells, is one of the targets in cancer research. Recently, a great deal of attention has been paid to the synthesis and function of actin‐targeting compounds and their use as effective molecular probes in chemical biology. In this study, we have developed an efficient synthesis of (?)‐doliculide, a very potent actin binder with a higher cell‐membrane permeability than phalloidin. Actin polymerization assays with (?)‐doliculide and two analogues on HeLa and BSC‐1 cells, together with a prediction of their binding mode to F‐actin by unbiased computational docking, show that doliculide stabilizes F‐actin in a similar way to jasplakinolide and chondramide C.     

乙酸正丁酯制备实验的改进

文章对有机化学实验教材中乙酸正丁酯的制备方法进行了改进,把环境友好催化剂纳米复合硅钨杂多酸引入到有机化学实验教学中．并与传统乙酸正丁酯实验（硫酸催化）进行比较。具有产品后处理简单,催化荆可重复使用,对环境污染小等优点。     

光气法合成邻羟基苯甲腈研究

邻羟基苯甲腈是一种重要的化工中间体,广泛应用于医药、农药、染料、高分子合成等工业生产中。研究了水杨酰胺和光气在甲苯溶液中合成邻羟基苯甲腈的反应,得出最佳反应条件为n(水杨酰胺)∶n(光气)=1∶1.2、反应温度90～100℃、反应时间5 h。经溶剂甲苯回收后,将邻羟基苯甲腈重结晶提纯,产品质量分数为95.1%,收率达92.3%。     

微波加热在化学反应中的应用进展

介绍了微波加热的基本原理,并就微波加热在有机合成、高分子合成及加工、无机合成、天然气转化等方面的最新应用情况进行了综述分析,指出应加强微波对化学反应作用机理的研究。     

连续流微反应技术在药物合成中的应用研究进展

基于微反应器的连续流微反应技术在化学制药行业还是相对较新的概念，相比于传统釜式合成方式，该反应技术具有传质传热效率高、本质安全、过程重复性好、产品质量稳定、连续自动化操作和时空效率高等诸多优势，其用于化学药物合成中的研究越来越多。本文综述了近年来连续流微反应技术在实现从起始原料到终端原料药或制剂的“端-到-端”连续合成制备方面的研究进展，以典型案例分析的方式具体阐明了它的技术优势和重要意义，分析总结了其应用于化学药物合成目前所存在的问题。总体来说，化学药物合成的工艺路线较长，各步反应间常存在体系兼容性、溶剂置换、分离纯化和加料顺序等方面的问题，造成各单步合成转化之间的工艺衔接和耦合后处理步骤是“端-到-端”多步连续流微反应技术的难点和挑战，亟待进一步发展。同时指出发展能与微反应器有效耦合的工艺衔接及后处理技术与装备将逐步成为该领域的研究热点。     

CFZ-86催化反应装置及其性能研究

本文介绍了用于催化剂评价和研究化学反应动力学的CFZ-86模型催化反应装置。其反应部分设计成4根反应管并联,可同时用作催化剂快速筛选;装置采用在线色谱分析,自动化程度较高;经实验考察表明,该装置操作稳定可靠,性能良好,实验结果精度高,可适用于实验室评价催化剂与催化反应动力学研究。     

丁苯那嗪的绿色合成工艺

提出了一种以水为反应介质合成治疗亨廷顿舞蹈病(Huntington’s disease, HD)药物--丁苯那嗪的新方法。以价廉易得的5-甲基-2-己酮为原料,先与二甲胺发生Mannich 反应,再与6,7-二甲氧基-3,4-二氢异喹啉盐酸盐在水介质中90℃经胺交换反应得到目标产物。通过实验优化合成路线,确定了各步反应最优的反应条件(反应时间、反应温度、摩尔收率)分别为：Mannich 反应,回流,5 h,55 %;胺交换反应,90 ℃,4 h,68 %。目标产物经1H NMR、IR、MS和元素分析确证表征。合成工艺简化,仅有两步反应;合成工艺绿色化,具有条件温和、操作简便、环境友好的优点。     

Oligomeric 1,4-phenyleneterephthalamide. Synthesis by interfacial polycondensation and structural properties

The synthesis of a fully aromatic oligoamide by low temperature interfacial polycondensation between terephthaloyl chloride and 1,4-phenylenediamine is reported. The reaction product was characterized with respect to its physical properties and chemical structure by infrared, X-rays, electron spectroscopy for chemical analysis (ESCA), and mass spectroscopic techniques. Elemental and thermal analysis, as well as viscosimetric and titrimetric methods were applied to evaluate the average molecular weight of the oligomer, whose chain length consists mainly of 3 to 4 monomeric units.     

Simple and reusable picoinjector for liquid delivery via nanofluidics approach

Precise control of sample volume is one of the most important functions in lab-on-a-chip (LOC) systems, especially for chemical and biological reactions. The common approach used for liquid delivery involves the employment of capillaries and microstructures for generating a droplet which has a volume in the nanoliter or picoliter range. Here, we report a novel approach for constructing a picoinjector which is based on well-controlled electroosmotic (EO) flow to electrokinetically drive sample solutions. This picoinjector comprises an array of interconnected nanochannels for liquid delivery. Such technique for liquid delivery has the advantages of well-controlled sample volume and reusable nanofluidic chip, and it was reported for the first time. In the study of the pumping process for this picoinjector, the EO flow rate was determined by the intensity of the fluorescent probe. The influence of ion concentration in electrolyte solutions over the EO flow rate was also investigated and discussed. The application of this EO-driven picoinjector for chemical reactions was demonstrated by the reaction between Fluo-4 and calcium chloride with the reaction cycle controlled by the applied square waves of different duty cycles. The precision of our device can reach down to picoliter per second, which is much smaller than that of most existing technologies. This new approach, thus, opens further possibilities of adopting nanofluidics for well-controlled chemical reactions with particular applications in nanoparticle synthesis, bimolecular synthesis, drug delivery, and diagnostic testing.

PACS

85.85.+ j; 87.15.hj; 82.39.Wj