DL-苏式-对甲砜基苯丝氨酸乙酯的合成及拆分

以对甲砜基苯丝氨酸铜为原料,浓硫酸为催化剂,考察了DL-苏式-对甲砜基苯丝氨酸乙酯的制备工艺。最佳的工艺条件为:n(对甲砜基苯丝氨酸铜)∶n(浓硫酸)∶n(乙醇)=1∶6∶50,反应温度83℃,反应时间10 h,0℃下析晶,氨析时的pH=7.5,在该条件下,DL-苏式-对甲砜基苯丝氨酸乙酯收率为92%。对酯化废液及氨析废液中的DL-苏式-对甲砜基苯丝氨酸乙酯进行回收,最终DL-苏式-对甲砜基苯丝氨酸乙酯的收率提高到98%左右。采用IR1、HNMR和HPLC对所合成的产物DL-苏式-对甲砜基苯丝氨酸乙酯进行了分析与表征。以D-酒石酸作为手性拆分剂,对DL-苏式-对甲砜基苯丝氨酸乙酯进行拆分,结果表明,拆分最佳工艺为:n(DL-苏式-对甲砜基苯丝氨酸乙酯)∶n(D-酒石酸)∶n(甲醇)=1∶1∶50,氨析过程中的pH=7.5时,D-苏式-对甲砜基苯丝氨酸乙酯收率为93%。     

对甲砜基苯丝氨酸铜合成的研究

以对甲砜基苯甲醛、甘氨酸、硫酸铜为原料,氨水为催化剂,研究了对甲砜基苯丝氨酸铜的合成工艺。试验结果表明,制备对甲砜基苯丝氨酸铜的最适宜工艺为：n(对甲砜基苯甲醛)∶n(甘氨酸)∶n(硫酸铜)∶n(水)为1∶ 11∶ 055 ∶170,温度50 ℃,pH值为9,反应30 h,收率为80%左右。采用薄层色谱（TLC）、液质联机（LC MS）以及红外光谱（IR）进行表征,探究并证实了该反应的机理并推测了所发生的副反应。     

邻硝基对甲砜基苯甲酸的合成

选用以对甲砜基甲苯为原料，在催化剂的作用下，硝化、氧化邻硝基对甲砜基苯甲酸；并对此方法进行了优化实验，找到了合成邻硝基对甲砜基苯甲酸最佳工艺条件，得到含量为≥98．0%的产品，收率≥80．0%。     

电氧化合成Co3+及其在对甲砜基苯甲酸制备中的应用

本文对Co3+的电氧化合成以及用作氧化对甲砜基甲苯合成对甲砜基苯甲酸进行了系统研究。研究表明，选用阳极二氧化铅、阴极铅为电极板，陶瓷膜作为阳离子交换膜，电解液浓度为C(Co2+)=0.5mol/L、C(硫酸)=4.0mol/L、C(硫酸铵)=0.15mol/L，电极间距d=2cm、电流密度J=350A/m2、电解温度t=10℃，电解液Co2+转化率可达80%，电解氧化电流效率67.5%。在进行对甲砜基甲苯的氧化时，控制电解液浓度为C(Co3+)=0.4mol/L、C(硫酸)=4.0mol/L、C(硫酸铵)=0.15mol/L，Co3+与对甲砜基甲苯的摩尔比n（Co3+）：n（对甲砜基甲苯）=6:1，反应温度30℃，反应时间30min，对甲砜基苯甲酸的收率可达97.8%，精制后纯度在98.5%以上。     

D-色氨酸的合成工艺研究

在甲醇钠碱性条件下,以芦竹碱和N-乙酰氨基丙二酸二乙酯为原料进行缩合反应,缩合产物在4%的氢氧化钠水溶液中选择性水解脱羧得到N-乙酰-DL-色氨酸,然后在10%氢氧化钠水溶液中水解得到DL-色氨酸。DL-色氨酸用D-酒石酸拆分,并在苯甲醛催化下实现不对称转化,得到D-色氨酸D-酒石酸盐,最后用三乙胺中和得到目标产物D-色氨酸。确定了缩合和拆分步骤的适宜工艺条件。缩合步骤:甲醇钠摩尔量为芦竹碱的20%,n(芦竹碱)∶(N-乙酰氨基丙二酸二乙酯)=1∶1.2;拆分步骤:乙酸为溶剂,70℃反应,苯甲醛摩尔量为DL-色氨酸的10%,n(DL-色氨酸)∶n(D-酒石酸)=1∶2。     

Co~(3+)的电氧化合成及其在对甲砜基苯甲酸制备中的应用

以七水硫酸钴、浓硫酸、硫酸铵为原料,电氧化合成Co3+,用Co3+氧化对甲砜基甲苯合成对甲砜基苯甲酸。考察了电极材料、电解温度、电流密度、硫酸浓度以及电解液循环套用对电极反应和硫酸浓度、Co3+与对甲砜基甲苯物质的量比对氧化反应的影响。结果表明,在选用阳极二氧化铅、阴极铅为电极板,陶瓷膜作为阳离子交换膜,电解液浓度为c(Co2+)=0.5 mol/L、c (硫酸)=4.0 mol/L、c (硫酸铵)=0.15 mol/L,电极间距(d)为2 cm、电流密度(J)为350 A/m2、电解温度(T)为10℃时,电解液Co2+转化率可达80%,电解氧化电流效率达67.5%。在进行对甲砜基甲苯的氧化时,控制电解液浓度为c(Co3+)=0.4 mol/L、c(硫酸)=4.0 mol/L、c(硫酸铵)=0.15 mol/L,n(Co3+)∶n(对甲砜基甲苯)=6∶1,使得反应温度为30℃,反应时间为30 min,对甲砜基苯甲酸的收率可达97.8%,精制后纯度在98.5%以上。     

气-液氧化制备2-硝基-4-甲砜基苯甲酸工艺的研究

以2-硝基-4-甲砜基甲苯为原料,应用空气-硝酸联合氧化法合成出2-硝基-4-甲砜基苯甲酸,研究了物料配比、反应温度、反应时间、硝酸的滴加速率、空气的加入速率等工艺参数对合成产品收率的影响,获得了较佳的合成工艺参数。放大实验结果表明,在最佳工艺条件下产品收率达到85%,纯度达到97.1%。     

K_2CO_3催化合成N-丙炔基邻苯二甲酰亚胺

用邻苯二甲酰亚胺和3-氯丙炔反应制备N-丙炔基邻苯二甲酰亚胺。以正交实验设计的方法对N-丙炔基邻苯二甲酰亚胺的合成反应温度、反应时间、投料比以及相转移催化剂进行工艺条件优化,得出最佳工艺条件是反应温度60℃、反应时间6h、n(邻苯二甲酰亚胺)∶n(碳酸钾)∶n(四丁基氯化铵)为1∶1.25∶0.05,收率91.7%。     

K2CO3催化合成N-丙炔基邻苯二甲酰亚脏

用邻苯二甲酰亚胺和3-氯丙炔反应制备N-丙炔基邻苯二甲酰亚胺.以正交实验设计的方法对N-丙炔基邻苯二甲酰亚胺的合成反应温度、反应时间、投料比以及相转移催化剂进行工艺条件优化,得出最佳工艺条件是反应温度60 ℃、反应时间6 h、n(邻苯二甲酰亚胺)∶n(碳酸钾)∶n(四丁基氯化铵)为1∶1.25∶0.05,收率91.7%.     

重铬酸钠氧化法合成2-硝基-4-甲砜基苯甲酸的研究

2硝基4甲砜基苯甲酸是一种重要的化学原料,广泛应用于农药、医药、染料。本研究以对甲砜基苯甲酸为原料,经硝化、重铬酸钠氧化,制得2硝基4甲砜基苯甲酸,两步反应总收率达80%,产品纯度≥99%。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料，介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比，介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序，对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.