点击化学法快速合成氨基酸功能化的环糊精聚轮烷

通过叠氮-炔环加成点击反应制备了各种氨基酸功能化的生物相容性β-环糊精封端的α-环糊精聚轮烷.利用FTIR和氢核磁共振谱对产物的结构进行了表征.结果证明对于空间位阻较小的分子,点击反应能够在很短的时间(几分钟)内达到近100%的转化率.点击化学为功能化聚轮烷的制备提供了快速有效的新途径.     

对甲酰基苯氧基甲基型聚苯乙烯树脂的简便快速制备

以Merrifield树脂为原料,家用微波炉为反应装置,在微波照射的相转移催化(MI-PTC)条件下,简便快速地合成了3种甲酰基功能化的交联聚苯乙烯树脂——对甲酰基苯氧基甲基树脂、对甲酰基-2-甲氧基苯氧基甲基树脂和对甲酰基-3-甲氧基苯氧基甲基树脂.在MI-PTC条件下,树脂制备过程所需的时间不超过1h,而传统加热制备方法则需要8h以上.实验中,微波输入功率为158W,反应过程用FTIR谱进行监测,碘化四丁基铵被考察为最好的相转移催化剂.该方法提供了一种反应条件温和、简便快速地制备功能化树脂的途径.     

A FACILE SYNTHESIS OF ARYL THIOCYANATES USING SODIUM PERBORATE

A simple and convenient synthesis of aryl thiocyanates in high yields using sodium perborate is described.     

HYPERVALENT IODINE IN SYNTHESIS. 61. REGENERATION OF CARBONYL FUNCTION FROM CARBONYL DERIVATIVES USING POLYMER-SUPPORTED PHENYLIODINE BIS(TRIFLUOROACETATE)

Polymer-supported phenyliodine bis(trifluoroacetate) was prepared and used in the regeneration of carbonyl function from carbonyl derivatives.     

A FACILE CONVERSION OF THE BAYLIS-HILLMAN ADDUCTS INTO TRIMETHYLSILYL ETHERS WITH HEXAMETHYLDISILAZANE CATALYSED BY IODINE

The hydroxy group of the Baylis-Hillman adducts was protected with trimethylsilyl (TMS) group using the reaction of adducts 1a–h with hexamethyldisilazane (HMDS) catalyzed by iodine under nearly neutral reaction conditions.     

HYPERVALENT IODINE IN SYNTHESIS. 83. PALLADIUM-CATALYZED CARBONYLATIVE COUPLING OF DIARYLIODONIUM SALTS MEDIATED BY INDIUM

ABSTRACT

In the presence of palladium catalyst and indium diaryliodonium salt; react with carbon monoxide under mild reaction conditions to give diaryl ketone; in moderate yields.     

利用碘的挥发性提高ICP-AES测定碘的灵敏度

将碘化物稀溶液酸化,加H_2O_2氧化I-离子成I_2。溶液雾化时,I_2易挥发,单位时间进入ICP炬量增加,大大提高了测碘的灵敏度。检出限达0.8ppm。用粗食盐溶液及自来水为基体,测碘的回收率为93～99％。     

A FACILE SYNTHESIS OF N-DIETHOXYPHOSPHORYLFORMAMIDINES

Abstract

The convenient synthesis of N-phosphorylated formamidines, 3 based on the reaction c diethyl(ethoxymethylene)phosphoramidate, 1 with primary and secondary amines is described.     

PREPARATION AND SOME CHEMISTRY OF TETRANEOPENTYLOXYPHENYLPHOSPHORANE AND TETRACYCLOPENTYLOXYPHENYLPHOSPHORANE

Abstract

The title compounds were prepared by allowing the appropriate dialkylphenylphosphonite to react with neopentyl and cyclopentyl benzenesulfenates. Extensive variable temperature ¹³C nmr studies on tetraneopentyloxyphenylphosphorane showed no changes. ¹⁸O labeled benzoic acid was allowed to react with tetraneopentyloxyphosphorane to give neopentyl benzoate. The isotope study shows that the benzoic acid attacks on the methylene carbon of the neopentyl moiety.     

A FACILE SYNTHESIS OF 3-GLYCOSYL-5-SUBSTITUTED-2-ISOXAZOLES

The 1,3-dipolar cycloaddition reaction between a 2-deoxy-D-aldose oxime (D-gluco or D-ribo) and an alkyne as dipolarophile (phenylacetylene, 2-propyn-1-ol, 3-chloro-1-propyne, or 3-bromo-1-propyne) is described. The new 3-glycosyl-5-substituted-2-isoxazoles are characterized physically and spectroscopically.     

点击化学法制备含有肉桂酸酯基团的线性聚合物的研究

利用点击化学方法合成了一种侧链上含有肉桂酸酯基团的线性聚合物,利用核磁共振(1H NMR)、红外光谱(FTIR)、凝胶渗透色谱(GPC)和示差扫描量热分析(DSC)等方法对该聚合物的结构和性能进行了表征。DSC谱图显示,在170℃附近出现一个明显的放热峰,通过进一步的实验证明,该放热峰是由聚合物侧链上残余的叠氮基团与肉桂酸酯基团上的碳碳双键发生反应引起的。另外,实验证明,通过稀盐酸处理,可以消除聚合物中残余的叠氮基团。     

光化学反应在分析化学中的应用研究 光激活产生碘测定食品中的抗坏血酸

本文探讨了酸性介质中于紫外光的照射下,利用光激活产生碘的光化学动力学法测定抗坏血酸的可能性。结果表明,在0.25mol/L的硫酸介质中,在过量碘化钾的存在下,抗坏血酸的含量与到达滴定终点的时间在较宽的浓度范围内呈良好的线性关系。用于蜂蜜,黄瓜、蕃茄及Vc药片等样品分析,其相对标准偏差均在1％以下,准确度令人满意。     

双功能催化剂体系催化乙烯原位聚合制备长链支化聚乙烯研究

以蒙脱土负载 β 二酮二氯化锆作为乙烯齐聚催化剂与Et(Ind) 2 ZrCl2 复合组成了原位双功能聚合催化体系 ,成功地以乙烯为唯一单体唯一反应釜制备长链支化聚乙烯 ,该催化剂体系具有乙烯共聚活性高 ,聚合物物性可调等优点     

MICROWAVE ASSISTED KNOEVENAGEL CONDENSATION: A FACILE METHOD FOR THE SYNTHESIS OF CHALCONES *

Microwave irradiation of aromatic aldehydes with acetophenones or malonic acid in presence of anhydrous zinc chloride was resulted exclusively chalcones and cinnamic acids respectively in high yields.

     

A FACILE SYNTHESIS OF AMINO-IMINOMETHANESULFONIC ACID

Aminoiminomethanesulfonic acid was conveniently obtained by oxidation of aminoiminomethanesulfinic acid with H₂O₂ in a high yield and good purity.     

A FACILE SYNTHESIS OF N-ARYL AZIRIDINES

Reaction of N-aryl-β-amino alcohols with p-toluenesulphonyl chloride under phase transfer catalytic condition gave the corresponding N-aryl aziridines in good yields, whereas N-alkyl-β-amino alcohol [for e.g., L-ephedrine] gave the corresponding N-tosyl derivative as the major product, along with the expected N-alkyl aziridines in lower yield.     

煤显微组分分子结构模型的量子化学研究

采用分子力学和半经验量子化学方法，研究了神木煤显微组分的分子结构模型，比较了镜质组和惰质组分子模型的能量构成、不同类型键的键长和键裂解能。研究结果表明，扭转能和范德华能是分子中的主要作用力，取代基对体系能量有明显影响，烷基取代基使体系能量增加，而苯基取代基使体系能量降低；脂肪C—C键长比芳香C—C键长长，说明脂肪C—C在受热过程中比芳香C—C更容易断裂分解。对各键裂解能的计算结果表明，Car—Cal键的裂解能高于Cal—Cal，Car—O醚键的裂解能高于Cal—O醚键。而惰质组结构模型中除C—O醚键外，各键的裂解能均高于镜质组，说明惰质组结构模型比镜质组有较高的热稳定性。     

组合化学中的聚合物载体研究进展

本文综述了目前实验室及市场上可用于固相组合合成的聚合物载体的种类、性质及应用。     

ON THE POSSIBILITY OF INFRARED LASER-INDUCED CHEMISTRY*

Abstract— –We examine whether chemical reactions can be selectively stimulated by the absorption of infrared photons which individually do not satisfy activation energy requirements. By a modification of available rate theory we demonstrate that a non-thermal enhancement of a chemical reaction is in principle possible, and is primarily dependent upon the extent to which a molecular mode can be coherently driven. An assumed coherent response to laser radiation leading to a minimally detectable rate enhancement places realistic constraints on the allowable magnitudes of vibrational and phase relaxation times for the mode. The inclusion of anharmonic limitations on the amount of energy stored in the mode results in the placement of more stringent though not impossible limitations on the relaxation times. A non-linear reaction rate dependence on light intensity suggests that a Q-spoiled laser be used. Optimum experimental conditions should involve the use of liquids at a temperature where thermal rates are just beneath the level of detection.