湿化学法合成纳米ZrB2粉末

本文利用ZrO2-B2O3-C体系中碳热还原的基本原理,分别使用正丙醇锆(Zr(OC3H7)4)、硼酸(H3BO3)和蔗糖(C12H22O11)为原料,采用溶胶-凝胶法合成了ZrB2纳米粉末。在实验设计过程中,首先使用化学修饰剂乙酰丙酮(acac)修饰Zr(OC3H7)4,目的是防止Zr(OC3H7)4的快速水解;其次,选用蔗糖作为碳源,是考虑到蔗糖热解时可以完全分解为碳,这样可以准确计算热解过程碳的生成量。结果表明:当起始原料nB/nZr=2.3、热解温度为1550℃时,通过溶胶-凝胶法可以成功合成单相ZrB2纳米粉末。分布均匀的颗粒形貌呈等轴状,平均尺寸约50 nm。     

Synthesis of Chiral 2‐Aroyl‐1‐tetralols: Asymmetric Transfer Hydrgenation of 2‐Aroyl‐1‐tetralones via Dynamic Kinetic Resolution

The dynamic kinetic resolution of 2‐aroyl‐1‐tetralones was achieved via asymmetric transfer hydrogenation using (S,S)‐RuCl(p‐cymene)TsDPEN (TsDPEN=N‐(tosyl)‐1,2‐diphenylethylenediamine) in formic acid/triethyl‐ amine (5:2, molar ratio), afforded the desired products in good yields (up to 85%) with diastereomeric ratio up to >99:1 and high enantiomeric excesses (up to >99%). The absolute configuration of major the product was confirmed by X‐ray crystal structure analysis.     

Bisabocurcumin, a new skeleton curcuminoid from the rhizomes of Curcuma longa L.

A new skeleton bisabolane-type sesquiterpene curcuminoid,bisabocurcumin(1),along with 5 known compounds,curcumin(2), demethoxycurcumin(3),bidemethoxycurcumin(4),(1E,4E)-1,5-bis(4-hydroxy-3-methoxyphenyl)-penta-1,4-dien-3-one(5),and (1E,4E)-1-(4-hydroxy-3-methoxyphenyl)-5-(4-hydroxy phenyl-)-penta-1,4-dien-3-one(6)were isolated from the rhizomes of Curcuma longa L.Their structures were determined on the basis of spectroscopic analysis.Bisabocurcumin(1) is firstly obtained from nature with a new skeleton combined by a bisabolane-type sesquiterpene and a 1,7-diphenylheptanoid through a C-C bond.     

FeBr_3-catalyzed dibromination of alkenes and alkynes

The dibromination of alkenes and alkynes with bromosuccinimide and sodium bromide catalyzed by FeBr₃ under mild conditions has been developed.The trans-dibromo compounds were exclusively obtained with excellent yields.     

Synthesis and characterization of novel conjugated polymers based on 3-cyclobutene-1,2-dione moiety

Three novel conjugated polymers bearing 3,4-bis（4-hexylthiophen-2-yl）-3-cyclobutene-1,2-dione unit in their main chain have been synthesized successfully in good yields through Suzuki or Stille coupling reaction.Their molecular structures have been confirmed by FT-IR,¹H NMR and ¹³C NMR.All these copolymers exhibit broad and strong absorption bands in UV-vis region,and their optical band gaps are calculated to be 1.6-2.0 eV.suggesting that they have good coverage with the solar spectrum.These polymers have good thermostability and solubility in common organic solvents.Moreover,all these objective macromolecules possess high electron affinity of～3.8 eV determined from cyclic voltammetry measurement,implying that they are potential n-type polymeric photovoltaic materials.     

Determination of metoprolol in rabbit blood using capillary electrophoresis with laser-induced fluorescence detection

This work described a sensitive method for determination of metoprolol in rabbit plasma.The method involved purification by ultrafiltration,derivatization with fluorescein isothiocyanate,determination by capillary electrophoresis(CE) coupled with laser-induced fluorescence(LIF) detector.Other components in plasma including a variety of amino acids and proteins did not interfere with the determination of metoprolol in experimental condition.The assay had a wide range(2.0-500 ng/mL) of linearity and a detection limit of 0.8 ng/mL.The intra- and inter-day precisions were satisfactory with relative standard deviation(RSD) less than 10.0%and accuracy within 10.0%.This method was successfully applied to pharmacokinetic study of metoprolol in rabbit blood.     

Two new diterpenoids from Suregada glomerulata(Blume) Baill

Two new diterpenoids,3,4,18β-cyclopropa-ent-abieta-8(14),13(15)-dien-16,12-olide(1) and 3-oxojolkinolide B(2),were isolated from the roots of Suregada glomerulata(Blume) Baill.Their structures were determined by spectroscopic evidences. Compound 2 showed moderate cytotoxicity.     

Synthesis and characterization of novel conjugated polymers based on 3-cyclobutene-l,2-dione moiety

Three novel conjugated polymers bearing 3,4-bis(4-hexylthiophen-2-yl)-3-cyclobutene-1,2-dione unit in their main chain have been synthesized successfully in good yields through Suzuki or Stille coupling reaction.Their molecular structures have been confirmed by FT-IR,~1H NMR and ~(13)C NMR.All these copolymers exhibit broad and strong absorption bands in UV-vis region,and their optical band gaps are calculated to be 1.6-2.0 eV.suggesting that they have good coverage with the solar spectrum.These polymers...     

厚朴酚合成方法的改进研究

本实验中,将2,2＇-联苯二酚与1-溴丁烷经Williamson反应后,利用该反应产物溴化钠在酸性条件下与溴酸钠反应生成初生态的溴作为溴源,溴代反应得到5,5＇-二溴-2,2＇-二丁氧基联苯.中间产物5,5＇-二溴-2,2＇-二丁氧基联苯制成Grignard试剂后与烯丙基溴反应生成5,5＇-二烯丙基-2,2＇-二丁氧基...     

多壁碳纳米管-酰基吡唑啉酮复合膜修饰电极测定异烟肼

报道了一种修饰电极--多壁碳纳米管-酰基吡唑啉酮复合膜修饰玻碳电极(MWNTs/HPMαFP/GCE ),研究了异烟肼在此修饰电极上的电化学行为及反应机理.与裸GCE和MWNTs/GCE相比,异烟肼在MWNTs/HPMαFP/GCE上的氧化峰电流和检测灵敏度大大提高,表明多壁碳纳米管和酰基吡唑啉酮产生了协同增效作用.在...