磷钼酸绿色催化合成香兰素缩1,2-丙二醇

在磷钼酸为催化剂的条件下,用香兰素与1,2-丙二醇反应合成香兰素缩1,2-丙二醇,将香兰素缩1,2-丙二醇通过气相色谱和液相色谱进行分析。在整个实验操作过程中,讨论了原料的配比、反应时间、反应温度、催化剂用量的影响,以及催化剂回收重复利用和产物的纯度以及结构的情况分析。结果表明:其较优反应条件为:n(香兰素)∶n(1,2-丙二醇)=1∶1.3,催化剂用量为反应物总质量的0.3%,带水剂为15mL环己烷,回流反应2h,产率达94.87%以上。     

氨基磺酸催化合成丁醛1,2-丙二醇缩醛

以氨基磺酸为催化剂,对以正丁醛和1,2-丙二醇为原料合成丁醛1,2-丙二醇缩醛进行了研究。较系统考察了醛醇摩尔比、催化剂的用量、反应时间、带水剂诸因素对缩醛反应的影响。实验结果表明,丁醛为0.2mol,n（丁醛）∶n（1,2-丙二醇）=1∶1.5,氨基磺酸1g,带水剂环己烷15mL,反应时间为60min时,产品的收率可达56.14%。     

Matrix resins based on bismaleimide–1,2-polybutadienes

Improved thermally stable matrix resins have been obtained by the incorporation of 1,2-polybutadiene in 4,4′-bismaleimidodiphenylmethane. The thermal curing was performed at 185–195°C for 2.5 h and at 230–235°C for 45 min to give tough crosslinked polymers. The thermal curing reaction was monitered using FT-IR and differential scanning calorimetry. Thermogravimetric analysis of the cured resins have shown improved thermal stability up to 490–480°C both in air and nitrogen atmospheres. The char yield obtained in nitrogen at 800°C was in the range of 50–49%. Graphite cloth laminates were prepared and tested. The laminates showed improved tensile strength over to parent bismaleimide. 1,2-Polybutadiene was hydrogenated using 10% palladized-charcoal. The resulting polymer was characterized by using IR and ¹H-NMR, which showed reduction of 15% pendent vinyl double bonds.     

Biosynthesis of (R)-1,2-phenylethanediol and (R)-4-chloro-1,2-phenylethanediol by using two recombinant cells expressing enantiocomplementary epoxide hydrolases

Enantioconvergent biosynthesis of (R)-phenyl-1,2-ethanediol and (R)-4-chlorophenyl-1,2-ethanediol using two types of recombinant Escherichia coli cells expressing epoxide hydrolase of Caulobacter crescentus (CcEH) and a triple-point mutated EH of Mugil cephalus was investigated. The CcEH gene in pET28b(+) was expressed at 15 °C, and the reaction conditions such as biocatalyst ratio, reaction temperature and detergent addition were optimized to give best enantiopurity and yield. When two recombinant E. coli cells were used in sequential mode, (R)-phenyl-1,2-ethandiol with 90% enantiopurity and 95% yield was obtained in batch reaction. From 100 mM racemic 4-chlorostyrene oxide, (R)-4-chlorophenyl-1,2-ethanediol with 92% enantiopurity and 71% yield could be obtained.     

天然橡胶/顺丁橡胶/1，2-聚丁二烯橡胶并用胶的性能研究

研究天然橡胶(NR)/顺丁橡胶(BR)/1,2-聚丁二烯橡胶(1,2-PBR)并用胶的硫化特性、物理性能及动态力学性能,确定适用于轮胎胎面胶的BR/1,2-PBR最佳并用比。结果表明:与NR或BR相比,1,2-PBR加工性能稍差。当BR/1,2-PBR并用比为25/5时,NR/BR/1,2-PBR并用胶的综合物理性能和抗湿滑性能较好;当BR/1,2-PBR并用比为15/15时,并用胶的压缩温升低,压缩永久变形最小,综合力学性能优异,更适合应用于轮胎胎面。     

Dehydrochlorination of propylene chlorohydrin with sodium hydroxide and with catholyte

Dehydrochlorination of an aqueous solution of propylene chlorohydrin with sodium hydroxide (12·5 and 30% by weight), with catholyte (5 or 10% by weight NaOH + 14% by weight NaCl) and with milk of lime (15% by weight) were compared. The use of catholyte (10% by weight NaOH + 14% by weight NaCl) enables propylene oxide to be obtained in a yield of 94·3%, with 100% conversion of chlorohydrin. The concentration of 1,2-propylene glycol in the waste is 0·07% by weight.     

废旧光盘化学处理工艺探讨及优化

针对废旧光盘的化学法处理,配制了次氯酸钠和氢氧化钠混合碱式盐洗脱液,剥离了印刷层、保护层,利用1,2-二氯乙烷溶解聚碳酸酯基盘,再用乙醇反沉淀,在1,2-二氯乙烷和乙醇混合废液中加入等体积水,将1,2-二氯乙烷和乙醇分离回收。实验表明:次氯酸钠和氢氧化钠质量比为6:4,洗脱液浓度为15%时洗脱效果较好,洗脱时间约35min。1,2-二氯乙烷溶解时间为5h,聚碳酸酯粗颗粒的回收率为75.4%,1,2-二氯乙烷回收率为75%。     

间歇出酶/出菌丝的培养方式对里氏木霉产纤维素酶的影响

以微晶纤维素和淀粉水解液作为碳源生产纤维素酶,在里氏木霉Rut C30分批补料生产纤维素酶的过程中通过间歇取出部分酶的培养方式保护纤维素酶。实验结果显示：采用间歇出酶培养方式,在分批补料3 d后,每1、2或者3天取出部分酶液。当平均每天取出15%的酶液,酶活显著增加,总纤维素酶酶活较单纯分批补料提高26.5%~32.6%,而总β-葡萄糖苷酶酶活提高超过46%;采用间歇出酶出菌丝培养方式,当每天取出15%的酶液时,纤维素酶产量比分批补料增长35.4%,去除和酶液等量的菌丝,酶活和分批补料相比增长32.5%,而且这两种培养方式所生产的纤维素酶的酶解效率高达82%,远超商品酶Celluclast（62.03%）。     

Separation of ethylene glycol, 1,2-butanediol and 1,2-propanediol with azeotropic distillation

1,2-butanediol (1,2-BDO) and 1,2-propanediol (1,2-PDO) are inevitably side produced in the ethylene glycol (EG) production processes from non-petroleum routes, but are very difficult to separate by the ordinary distillation method because of the closeness of their boiling temperatures to EG, thus compromise the economy of these processes. The azeotropic distillation process using 1-octanol (CPO) as an entrainer to separate EG and 1,2-BDO mixture with or without 1,2-PDO was studied in this paper. Four binary vapour–liquid equilibrium data of EG-1,2-BDO, EG-CPO, 1,2-BDO-CPO, and 1,2-PDO-CPO were measured using an Ellis equilibrium kettle and regressed with the thermodynamic model of non-random two liquid to obtain the corresponding binary interaction parameters. On this basis, azeotropic distillations with CPO as an entrainer were designed to separate EG and 1,2-BDO with or without 1,2-PDO. The complete separation processes, including the azeotropic distillation and CPO recovery process consisting of extraction with H₂O and subsequent distillation, were simulated and optimized with Aspen Plus for both the EG-1,2-BDO binary mixture and the EG-1,2-BDO-1,2-PDO ternary mixture. The simulation results show that the azeotropic distillation method with CPO as an entrainer can effectively separate the mixture of EG-1,2-BDO and EG-1,2-BDO-1,2-PDO, achieving EG of 99.90% purity with 99.98% recovery and 1,2-BDO of 99.30% purity with 99.45% recovery for the binary mixture, and achieving EG of 99.90% purity with 99.80% recovery, 1,2-BDO of 99.35% purity with 99.35% recovery, and 1,2-PDO of 90.59% purity with 94.38% recovery for the ternary mixture. These processes are promising for industrial application and can significantly improve the economy of non-petroleum EG production.     

维生素B1催化制备2-噻吩偶姻的研究

以维生素B1为催化剂,在三乙胺为碱的条件下,催化2-噻吩甲醛发生安息香缩合反应制备噻吩偶姻,产率15％。     

苯乙炔的合成研究

苯乙烯与溴在四氯化碳中于１０～１５℃反应生成１,２ 二溴乙苯,后者与氢氧化钾在甲醇中回流脱溴化氢生成苯乙炔,总收率６０％。     

Photopolymerization of 1,2-epoxypropane and 1,2-epoxybutane by arenediazonium salts: evidence for anion dependence of the extent of polymerization

The rates and extents of polymerization of 1,2-epoxypropane and 1,2-epoxybutane, induced by photolysis of dilute concentrations of salts of 2,5-diethoxy-4-tolylthiobenzenediazonium ion with various Lewis acids (SbF^?₆, PF^?₆, BF^?₄ etc.) have been determined by viscosity, ¹H n.m.r. and polymer isolation methods. A clear dependence exists of the degree of conversion on the anion: thus SbF^?₆ salt yields up to 100% high polymer, PF^?₆ salt yields c. 20% high polymer, while BF^?₄ salt yields small conversions (2%, but increasing to 15–18% at high initiator concentrations) which consists almost entirely of oligomers, mainly the cyclic tetramer.     

阳离子交换树脂催化合成苹果酯- B的研究

采用强酸性阳离子交换树脂为催化剂,以乙酰乙酸乙酯、1,2-丙二醇为原料合成苹果酯-B。分别研究了反应温度、反应时问、原料配比和催化剂用量等条件对合成反应的影响。得到了合成苹果酯-B最适宜的条件：104℃,反应3h,乙酰乙酸乙酯与1,2-丙二醇摩尔比为1：1．45,带水剂环己烷为15mL（乙酰乙酸乙酯为0．15mol的情况下）,强酸性阳离子交换树脂的用量为总物料质量的5．25％。苹果酯-B的收率可达到96．8l％,产品中苹果酯-B质量分数为99．8％。     

Feeding Deterrence and Detrimental Effects of Pyrrolizidine Alkaloids Fed to Honey Bees (<Emphasis Type="Italic">Apis mellifera</Emphasis>)

Recent studies have shown the occurrence of plant derived pyrrolizidine alkaloids (PAs) in retail honeys and pollen loads, but little is known about how these compounds influence the fitness of foraging honey bees. In feeding experiments, we tested a mix of tertiary PAs and the corresponding N-oxides from Senecio vernalis, pure monocrotaline, and 1,2-dihydromonocrotaline in 50% (w/w) sucrose solutions. The bees were analyzed chemically to correlate the observed effects to the ingested amount of PAs. PA-N-oxides were deterrent at concentrations >0.2%. 1,2-Unsaturated tertiary PAs were toxic at high concentrations. The observed PAs mortality could be linked directly to the presence of the 1,2-double bond, a well established essential feature of PA cytotoxicity. In contrast, feeding experiments with 1,2-dihydromonocrotaline revealed no toxic effects. Levels of less than 50 μg 1,2-unsaturated tertiary PAs per individual adult bee were tolerated without negative effects. PA-N-oxides fed to bees were reduced partially to the corresponding tertiary PAs. Unlike some specialized insects, bees are not able to actively detoxify PAs through N-oxidation. To gain insight into how PAs are transmitted among bees, we tested for horizontal PA transfer (trophallaxis). Under laboratory conditions, up to 15% of an ingested PA diet was exchanged from bee to bee, disclosing a possible route for incorporation into the honey comb. In the absence of alternative nectar and pollen sources, PA-containing plants might exhibit a threat to vulnerable bee larvae, and this might affect the overall colony fitness.     

Solubilization and partial purification of cholinephosphotransferase in hamster tissues

CDP choline:1,2-diacylglycerol cholinephosphotransferase (EC 2.7.8.2) is located on the cytoplasmic side of the endoplasmic reticulum, and catalyzes the final step in the synthesis of phosphatidylcholine via the CDP choline pathway. The enzyme was solubilized from hamster liver microsomes by 3% Triton QS-15, and partially purified by DEAE-Sepharose chromatography and Sepharose 6B chromatography. The microsomal and partially purified enzymes displayed similar pH profile, and both showed absolute requirement for Mg⁺⁺ or other divalent cations. The Km values of CDP choline were similar between microsomal and partially purified enzyme, whereas the Km value for diacylglycerol was substantially lowered when the enzyme was partially purified. Hamster heart cholinephosphotransferase was not solubilized by Triton QS-15.     

Enantioselective Hydrogenation of Aromatic Ketones Catalyzed by a Mesoporous Silica‐Supported Iridium Catalyst

A mesoporous, silica‐supported, chiral iridium catalyst with a highly ordered dimensional‐hexagonal mesostructure was prepared by postgrafting the organometallic complex (1‐diphenylphosphino‐2‐triethylsilylethane)[(R,R)‐1,2‐diphenylethylenediamine]iridium chloride {IrCl[PPh₂(CH₂)₂Si(OEt)₃]₂[(R,R)‐DPEN] (DPEN=1,2‐diphenylethylenediamine)} on SBA‐15 silica. During the asymmetric hydrogenation of various aromatic ketones under 40 atm of hydrogen, the mesoporous, silica‐supported, chiral iridium catalyst exhibited high catalytic activity (more than 95% conversions) and excellent enantioselectivity (up to more than 99% ee). The catalyst could be recovered easily and used repetitively seven times without significantly affecting the catalytic activity and the enantioselectivity.     

Lack of dietary adaptation of intestinal 2-monoglyceride acyl transferase

Acylation of 2-monopalmitin with (1-¹⁴C) palmityl-coenzyme A was studied with microsomal fractions isolated from the intestinal mucosa of both hamsters and rats. Microsomes from hamster intestinal mucosa yielded equal molar amounts of 1,2-diglycerides and triglycerides, while those from rats synthesized more 1,2-diglycerides (70%) than triglycerides (30%). Although the enzyme system from the hamster was almost twice as active (55 nmoles monoglyceride acylated/min/mg protein) as that from the rat (31 nmoles monoglyceride/acylated/min/mg protein), there was essentially no difference in the rates of acylation when animals were (A) fasted for 3 days, (B) fed a high fat diet (15% safflower oil), or (C) fed a high carbohydrate diet for 5 days.     

水溶性二羟丙基壳聚糖的制备及性能研究

以壳聚糖(Chitosan,CTS)为原料进行改性制备成水溶性更为优良的多羟基壳聚糖。首先利用α-氯甘油醇与NaOH反应生成醚化剂——缩水甘油(glycidol)。再用异丙醇溶液为反应体系,对壳聚糖进行碱化、醚化、中和以及提纯处理,得到了二羟丙基壳聚糖。最佳反应条件为:壳聚糖2 g,NaOH 30%～40%,缩水甘油15 mL,温度60℃,反应时间8 h。     

Cyclodehydration reactions of methyl 9,10-; 10,12-; and 9,12-dioxostearates with 1,2-diaminoethane under ultrasonic irradiation

Reaction of methyl 9,10-dioxostearate (1) and 9,12-dioxostearate (2) with 1,2-diaminoethane under concomitant ultrasonic irradiation (10–15 min, 60°C) in water furnished the corresponding 2,3-dihydropyrazine (4, 79%) and 1,2,3,4-tetrahydro-1,4-diazocine (5, 70%) derivatives, respectively. Reaction of methyl 10,12-dioxostearate (3) with 1,2-diaminoethane was successful only when glacial acetic acid was used instead of water under ultrasonic irradiation (4×10 min, 70°C) to give a 2,3-dihydro-1H-1,4-diazepine (6, 95%) derivative. The structures of these novel six-membered (4), seven-membered (6), and eight-membered (5) N-heterocyclic fatty ester derivatives were confirmed by a combination of infrared, nuclear magnetic resonance spectroscopic and mass spectral analyses.     

A Synthetic Approach to Oligomeric Phenylethynylsilylenes

Oligomers consisting of alternating phenylethynyl and monosilyl or disilanyl moieties were synthesized in 15–64% precipitated yields by the reactions of dilithiated ethynylbenzene with dichlorodimethylsilane, dichlorodiphenylsilane, and 1,2-dichloro-1,1,2,2-tetramethyldisilane. Degrees of polymerization were fairly low due to chain termination reactions involving the deprotonation of ethynyl groups by aryllithium species. The presence of butyl chain ends was confirmed by ¹H and ²⁹Si NMR spectroscopy. ²⁹Si NMR spectroscopy was utilized to illustrate the random pattern of connectivity along the oligomer backbones. The oligomers exhibit fluorescent behavior in solution.