TS-1分子筛催化苯乙酮氨肟化反应

研究了钛硅分子筛(TS-1)催化苯乙酮氨肟化反应中溶剂、反应温度、助催化剂(氧化铝和乙酸铵)、氨水及H2O2用量对反应的影响. 结果表明,适宜的溶剂为乙醇,最佳反应温度为80℃,助催化剂乙酸铵在溶液中的浓度不低于0.43%(w)时能显著提高苯乙酮氨肟反应的转化率,而Al2O3的作用不明显. 为了获得较高的转化率,物料中NH3/苯乙酮以及H2O2/苯乙酮的摩尔比应分别控制在2.00和1.27以上.     

盐酸氯美噻唑的合成工艺改进

研究了以d一乙酰基-1-丁内酯为原料,“一锅法”合成3一溴-3-乙酰基丙醇,再与硫脲环合得到2-氨基-4-甲基-5-（p-羟乙基）噻唑。最后两步采用现有工艺,经重氮化、还原、氯化合成了目标产物盐酸氯美噻唑。在较佳反应条件下,四步反应总收率达39．8％。产品及重要中间体结构经核磁共振确认。用双氧水和溴化氢替代传统的卤化试剂磺酰氯,以水为溶剂,“一锅法”合成3一溴一3一乙酰基丙醇。环合反应也在溶剂水中进行。整个过程所用原料廉价,反应相对高效、绿色。     

1-氯甲酰基-3-乙酰基咪唑烷酮合成新方法研究

采用乙酰基苯并三氮唑以及双（三氧甲基）碳酸酯作为原料,合成了酰脲类青霉素的关键中间体1-氯甲酰基-3-乙酰基咪唑烷酮。实验结果表明,合成中间产物乙酰基咪唑烷酮时,甲苯为溶剂时反应收率最高,使用K2CO3最适宜且n（咪唑烷酮）：n（K2CO3）=1：1时反应收率最高;合成1-氯甲酰基-3-乙酰基咪唑烷酮时,最适宜以氯仿为溶剂、三乙胺为催化剂,且n（乙酰基咪唑烷酮）：n（BTC）=1：0．45时收率最高。产品总收率达到80％。该方法反应条件温和、活性好、产品纯度高、收率高,并对环境友好。     

一种改进的制备间硝基苯乙酮方法

以KNO3和磷酸构成的复合硝化剂对0.1 moL苯乙酮进行硝化,元素分析、FTIR和1HNMR的分析结果表明,硝化得到的产物为间硝基苯乙酮。研究表明,苯乙酮以KNO3-磷酸复合硝化剂硝化时,反应具有性能缓和、安全性高、可控性强的特点,反应温度可由混酸硝化时的-15~-10℃提高至80~90℃,且氧化副反应的发生程度显著降低,苯乙酮的可利用率提高。在n(硝酸钾)/n(苯乙酮)为1.5~1.7、n(磷酸)/n(硝酸钾)为1.6~2.0、反应温度为80~90℃、反应时间为7.0~8.0 h时,间硝基苯乙酮收率可达45%左右。     

1-Acyl-2-acetyl-sn-glycero-3-phosphocholine from stimulated human polymorphonuclear leukocytes

1-Acyl-2-acetyl-sn-glycero-3-phosphocholine (1-acyl-2-acetyl GPC) was found in the fraction of platelet-activating factor obtained from stimulated human polymorphonuclear leukocytes (PMN). The amount of 1-acyl-2-acetyl GPC obtained from 1×10⁷ PMN stimulated with ionophore A23187 at 37 C for 15 min ranged from 8 to 56 pmol (32±10 pmol, mean±standard error; n=4). The main species was 16∶0 palmitoyl (17±5 pmol), followed by 18∶0 stearoyl (8±3 pmol) and 18∶1 oleoyl (7±3 pmol). Although the physiological significance is unknown, 1-acyl-2-acetyl GPC was always detected when 1-alkyl-2-acetyl GPC was detected.     

雷洛昔芬中间体4-甲氧基-α-[(3-甲氧基苯基)硫代]苯乙酮含量的反相高效液相色谱测定

采用反相高效液相色谱法,以v(甲醇)v∶(水)=802∶0作为流动相,用C18柱和二极管阵列检测器(DAD,282nm),测定4-甲氧基--α[(3-甲氧基苯基)硫代]苯乙酮的含量。结果表明,4-甲氧基--α[(3-甲氧基苯基)硫代]苯乙酮在0.02～0.90μg内呈良好的线性关系,r=0.99999。该方法灵敏、快速、准确,可用于4-甲氧基--α[(3-甲氧基苯基)硫代]苯乙酮含量的测定。     

香料苯乙酮环乙二缩酮的催化合成研究

以氨基磺酸为催化剂,通过苯乙酮和乙二醇反应合成苯乙酮环乙二缩酮。探讨了氨基磺酸的催化活性,研究了催化剂用量、酮醇物质的量比和反应时间等对产物收率的影响。实验结果表明,氨基磺酸是合成苯乙酮环乙二缩酮的良好催化剂,最佳反应条件：n(酮)∶n(醇)=1∶1.3,催化剂用量0.6 g·(0.2 mol-苯乙酮)^-1,反应时间160 min,产物收率可达75.6%     

复合固体超强酸SO2-4-/Fe2O3/ZnO/ZrO2催化合成苯乙酮1,3-丙二醇缩酮

通过沉淀、老化、过滤、洗涤、干燥、浸渍和焙烧等过程,由Fe(NO3)3·9H2O、Al(NO3)3·9H2O和ZrOCl2·8H2O制备SO2-4/Fe2O3/ZnO/ZrO2催化剂,研究酮与醇物质的量比、反应时间、带水剂用量和催化剂用量等因素对产品收率的影响.结果表明,SO2-4/Fe2O3/ZnO/ZrO2是合成苯...     

Unexpected Inversion in Enantioselectivity in the Hydrogenation N-acetyl Dehydrophenylalanine Methyl Ester using Cinchona-Modified Pd/Al2O3 catalyst

The enantioselective hydrogenation of N-acetyl dehydrophenylalanine methyl ester (NADPME) to N-acetyl phenylalanine methyl ester is investigated using cinchona-modified Pd/Al₂O₃ catalysts. The catalyst was prepared using deposition-reduction and was evaluated for the reaction using methanol as solvent with various cinchonine alkaloid/NADPME molar ratios. Enantioselectivity was sensitive to this ratio. For cinchonine at low cinchonine:NADPME molar ratios the S-N-acetyl phenylalanine methyl ester was formed with low enantioselection, and as the cinchonine:NADPME ratio was increased the reaction became less enantioselective. In the extreme the solubility of cinchonine limited the extent of the experimental conditions that could be explored. As expected cinchonidine modified Pd/Al₂O₃ initially gave R-N-acetyl phenylalanine methyl ester, again with low enantioselection. However, as the cinchonidine:NADPME molar ratio was increased the reaction initially became racemic and then was selective to the formation of S-N-acetyl phenylalanine methyl ester. This unexpected inversion in the sense of enantioselection was observed in a range of solvents.     

超声波辅助吗啡啉催化Knoevenagel缩合制备3-乙酰基香豆素

研究了吗啡啉催化水杨醛和乙酰乙酸乙酯的Knoevenagel缩合制备3-乙酰基香豆素。探讨了溶剂、碱的种类、催化剂用量、反应时间对3-乙酰基香豆素产率的影响,结果表明,以乙醇为溶剂,在超声波的辅助下,添加碳酸钠作为助催化剂,吗啡啉催化水杨醛和乙酰乙酸乙酯室温反应20 min,即以91%的产率得到了3-乙酰基香豆素。采用NMR、IR表征了产物结构,并对反应催化机理进行了探讨。     

新型含吡啶环二胺及其可溶透明性氟化聚酰亚胺的合成与表征

以4-三氟甲基苯甲醛和3-(4-硝基苯氧基)苯乙酮(m,p-NPAP)为原料,通过改进的Chichibabin反应制备了硝基化合物4-(4-三氟甲基苯基)-2,6-双[3-(4-硝基苯氧基)苯基]吡啶(m,p-3FPNPP),再用Pd/C和水合肼将m,p-3FPNPP进行还原,成功制备了一种新型含吡啶环的芳香二胺4-(4-三氟甲基苯基)-2,6-双[3-(4-胺基苯氧基)苯基]吡啶(m,p-3FPAPP)。以m,p-3FPAPP作为二胺,3,3′,4,4′-二苯醚四羧酸二酐(ODPA)作为二酐,N,N-二甲基甲酰胺(DMF)为溶剂,通过常规的两步法,经热或者化学亚胺化形成聚酰亚胺,制得了一种新型的含吡啶环聚酰亚胺。所得聚酰胺酸和聚酰亚胺的粘度分别为0.78 dL/g和0.65 dL/g。化学亚胺化所得的聚酰亚胺速溶于常见有机溶剂如DMF、N,N-二甲基乙酰胺(DMAc)、N-甲基-2-吡咯烷酮(NMP)、四氢呋喃(THF)等。制得了柔韧的聚酰亚胺膜,膜有很好的热稳定性,玻璃化转变温度(Tg)为234.4℃,氮气氛中10%失重温度为575.3℃,膜有很好的光学透明性,截止波长为369 nm,同时,膜还有较好的力学性能,拉伸强度为96.4 MPa,拉伸模量为1.63 GPa,断裂伸长率为9.2%,膜的吸水率为0.68%。     

复合固体超强酸SO42-/Fe2O3/Al2O3/ZnO/ZrO2催化剂的制备及其催化性能

沉淀法由Fe（NO3）3、Al（NO3）3、Zn（Ac）2、ZrOCl2和H2 SO4制备SO42-/Fe2O3/Al2O3/ZnO/ZrO2催化剂,用于催化合成苯乙酮乙二醇缩酮,研究了醇酮摩尔比、反应时间、带水剂用量、催化剂用量等对产品收率的影响.结果表明,在n（苯乙酮）∶n（乙二醇）=1∶1.2,苯乙酮物质的量为0.2 mol,催化剂的量是反应物料总质量的1.5％,带水剂甲苯20 mL,100～120℃回流反应60 min的条件下,苯乙酮乙二醇缩酮的收率达98.8％.     

α-乙酰氧基苯乙酮的合成研究

用三氟化硼乙醚为催化剂,以苯乙酮和乙酸(也是溶剂)为原料,利用碘酰苯为氧化剂"一锅法"合成了α-乙酰氧基苯乙酮。研究了温度和催化剂用量对目标产物的影响,优化的工艺条件为:n(苯乙酮)∶n(三氟化硼乙醚)∶n(碘酰苯)=1∶3∶1.2,反应温度50℃,反应时间6h,此条件下产品收率72%。     

强酸性阳离子交换树脂催化合成苯乙酮环乙二缩酮的研究

在强酸性阳离子交换树脂催化剂存在下,以苯乙酮、乙二醇为原料合成苯乙酮环乙二缩酮,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。该方法合成苯乙酮环乙二缩酮的最佳工艺条件是:反应温度为95℃,反应时间2.5 h,n(苯乙酮)∶n(乙二醇)=0.2∶0.28;强酸性阳离子交换树脂用量为1.5 g;带水剂环己烷为40 mL(苯乙酮为0.2 mol的情况下)。苯乙酮环乙二缩酮的收率可达到96.25%,产品纯度99.5%以上。催化剂不经处理可循环使用多次。该催化剂具有价廉易得、催化活性好、不腐蚀设备、无环境污染等优点。     

从肉桂酸生物发酵液中提取苯乙酮的研究

开展了从肉桂酸生物转化合成苯乙酮过程中的发酵液提取苯乙酮的研究,通过比较溶剂萃取法和水蒸汽蒸馏法提取的特点,提出了水蒸汽蒸馏-溶剂萃取偶合法从发酵液提取苯乙酮的提取分离方法。结果表明,用溶剂萃取法时,经过乙酸乙酯和调节pH前处理、环己烷萃取、浓缩等步骤,苯乙酮的萃取得率为89.0%,萃取溶剂使用量为1 mL发酵液需要1 mL有机溶剂(乙酸乙酯与环己烷之和);而用水蒸汽蒸馏-溶剂萃取偶合法萃取得率为92.1%,萃取溶剂使用量为1 mL,发酵液仅需0.1 mL乙酸乙酯。     

Formation of a thiamine disulfide complex with fatty acid: Mechanism of formation of the complex

The formation of complexes between thiamine disulfide (TDS) orO-acetyl thiamine disulfide (O-acetyl TDS) and fatty acid or fatty acid methyl ester in methanol has been studied by fluorescence quenching and¹³C NMR relaxation (T₁) measurements. The association constants (K-values) of TDS andO-acetyl TDS with fatty acids (from 11∶0 to 18∶0, and 18∶1, 18∶2, 18∶3 and 20∶4) and fatty acid methyl esters have been determined. These values do not depend on either the number of carbon atoms or the degree of unsaturation of the fatty acid. The K-values of TDS andO-acetyl TDS with fatty acid were 7.8 M⁻¹ and 5.1 M⁻¹, respectively. The K-values of TDS andO-acetyl TDS with fatty acid methyl ester were very small. These results show that the-OH moiety in TDS and the-COOH moiety in the fatty acid are necessary for formation of the complex     

Triphenyltin (IV) derivatives of N-acetyl amino acids,N-acetyl dipeptides and tripeptides: Preparation,NMR investigations and NMR spectroscopic resolution of the enantiomeric composition

Triphenyltin(IV) derivatives of N-acetyl amino acids ( 1a–g ) and N-acetyl di- ( 2a–f ) or tripeptides ( 3 ) mostly in the (L )- and the racemic (DL )-form have been prepared from bis(triphenyltin)oxide and the appropriate N-acetyl amino acid or N-acetyl peptide using various dehydrating agents. The compounds were characterized by NMR spectroscopy and elemental analysis. These compounds were studied at different concentrations and temperatures, revealing a strong self-association tendency. NMR investigations were undertaken in order to highlight preferred conformations of the peptide derivatives due to possible strong intramolecular associations between tin and nucleophilic donor atoms of the peptide moiety in weakly polar solvents. No preferred conformation was found which was in accordance with the underivatized peptides. The enantiomeric composition was determined by means of ¹H NMR spectroscopy using (−)-quinine hydrochloride and S-(−)-1-phenylethylamine as chiral solvating agents.     

Responses of Female Orange Wheat Blossom Midge, Sitodiplosis mosellana, to Wheat Panicle Volatiles

Air entrainment samples of volatiles from panicles of intact wheat, Triticum aestivum, cultivar 'Lynx' were collected at the ear emergence/early anthesis growth stage. In an olfactometer bioassay, both freshly cut panicles and an air entrainment sample were found to attract female orange wheat blossom midge adults, Sitodiplosis mosellana. Coupled gas chromatography-electroantennography (GC-EAG) analyses of panicle volatiles located six electrophysiologically active components. These were identified by coupled gas chromatography-mass spectrometry and coinjection with authentic standards, on polar and nonpolar GC columns, as acetophenone, (Z)-3-hexenyl acetate, 3-carene, 2-tridecanone, 2-ethyl-1-hexanol, and 1-octen-3-ol. Although none of these was active when presented individually at the levels present in the entrainment sample, acetophenone, (Z)-3-hexenyl acetate, and 3-carene were active in the olfactometer when presented at a higher dose of 100 ng on filter paper. However, the six-component blend and a blend of acetophenone, (Z)-3-hexenyl acetate, and 3-carene, in the same ratio and concentration as in a natural sample, was as attractive to female S. mosellana as the whole air entrainment sample.     

Inclusive separation of acetophenone from petrochemical by‐product with 1‐phenylethanol via noncovalent interactions

Separation of the barely studied mixture of acetophenone and 1‐phenylethanol, a typical by‐product obtained by oil refinery plant, based on the preferential affinity of β‐cyclodextrin (abbreviated as β‐CD) for acetophenone is focused. To demonstrate the potential application of β‐CD for separation of acetophenone from 1‐phenylethanol, the noncovalent interactions of β‐CD with acetophenone and 1‐phenylethanol were compared from thermodynamic and conformational points of view. For the purpose of separation, a multicomponent coprecipitation technique has been established based on the selective noncovalent binding property of β‐CD, which has been proved rigorously. Under the optimized conditions, the acetophenone/1‐phenylethanol equimolar binary mixture can be separated with a separation factor >37. For the petrochemical by‐product, which contains 74.93 wt % of acetophenone, 17.79 wt % of 1‐phenylethanol, and other minor compounds, expanding the separation scale, content of acetophenone in complex can get 99.2%, and the separation efficiency of β‐CD kept stable after recycling twice. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2962–2975, 2014     

苯乙酮1，2-丙二醇缩酮的合成研究

以强酸性阳离子交换树脂为催化剂,通过苯乙酮和1,2-丙二醇反应合成苯乙酮1,2-丙二醇缩酮,系统的研究了酮醇物质的量之比、催化剂用量和反应时间等因素对产品收率的影响。结果表明：在酮醇物质的量比为1：2,催化剂用量为反应物总质量的0．6％,环己烷为带水剂,反应时间3h的优化条件下,产率达79．8％。