乙酸-三氟化硼乙醚混合质子电解质

乙酸和三氟化硼乙醚(BFEE)本身离子电导率很低, 向乙酸中加入少量BFEE可以形成良好的混合质子电解质溶液. 随着乙酸中BFEE浓度的变化, 混合电解质溶液的离子电导率迅速上升, 当BFEE摩尔分数为65%时具有最大值, 达5800 μS/cm. 红外光谱和¹H NMR研究表明混合电解质中的主要导电离子为CH₃COOH₂^＋和CH₃COOBF₃^－.     

1,8-亚乙基萘在三氟化硼乙醚-聚乙二醇中的电化学聚合

在三氟化硼乙醚(BFEE)-聚乙二醇(分子量400,PEG400)混合电解质溶液中,1,8-亚乙基萘直接阳极氧化聚合可以获得自支撑聚(1,8-亚乙基萘)膜.单体在三氟化硼乙醚+10%PEG400中的起始氧化电位为0.95 Vversus SCE,远低于单体在0.1 mol.L-1四氟化硼四丁基胺-乙腈溶液中的起始氧化电位(1.38 VversusSCE).同时PEG400的加入可以有效改善单体在三氟化硼乙醚中的溶解性.UV-Vis,FTIR和1H-NMR确定了1,8-亚乙基萘在4,5位聚合,荧光光谱表明固态及可溶聚(1,8-亚乙基萘)膜是蓝色发光材料.     

ELECTROCHEMICAL COPOLYMERIZATION OF DIBENZOFURAN AND 3-METHYLTHIOPHENE IN BORON TRIFLUORIDE DIETHYL ETHERATE

The copolymerization of dibenzofuran(DBF)and 3-methylthiophene(MET)was successfully achieved electrochemically by direct anodic oxidation of the monomer mixtures in boron trifluoride diethyl etherate.The effects of applied polymerization potential and the monomer concentration ratios on the copolymerization were investigated by linear sweep voltammetry and cyclic voltammetry(CV).The structure of copolymer films were investigated by UV-Vis,infrared spectroscopy,thermal analysis.As-formed novel copolymers ...     

2-亚磷酸二乙酯基杂环烯酮缩胺类化合物的合成

用廉价易得原料Mn(OAc)2-KMnO4体系代替昂贵的Mn(OAc)3催化二甲缩硫醚(1)与亚磷酸二乙酯反应获得结构新颖的2-亚磷酸二乙酯基缩硫醚化合物2a～2d.然后,化合物2a～2d与二胺类化合物3反应以较高产率合成了一系列2-亚磷酸二乙酯基杂环烯酮缩胺(4).     

纳米复合固体超强酸S_2O_8~(2-)/CoFe_2O_4催化合成癸二酸二乙酯

将硫酸钴、硫酸亚铁在NaOH溶液中与NaHCO3反应制得碱式碳酸盐前驱体 ,后者用 (NH4 ) 2 S2 O8浸渍、干燥 ,再经 5 0 0℃焙烧得到固体超强酸催化剂S2 O2 -8/CoFe2 O4 。产物经XRD、TEM、BET、TG DTA及化学法等检测 ,含硫量 4 5 2 % ,粒径为 4 2nm ,比表面积为 1 4 6m2 /g ,粒度均匀。催化剂的酸强度处于 -1 6 0 2和-1 4 5 2之间。以该固体酸为催化剂 ,由癸二酸和无水乙醇合成了癸二酸二乙酯。最佳反应条件为 :n(醇 )∶n(酸 ) =4 0∶1 0 ,癸二酸 0 1mol,催化剂 1 0 g ,反应时间 2 5h。在此反应条件下 ,酯化率可达 93 6%。     

白酒中二元酸二乙酯的固相微萃取与气相色谱联用快速测定

应用固相微萃取 (SPME)和气相色谱联用 ,以十四醇为内标 ,建立了快速测定豉香型白酒中庚二酸二乙酯、辛二酸二乙酯和壬二酸二乙酯 (统称二元酸二乙酯 )的方法;采用正交设计研究了萃取时间、解吸时间、盐效应等对萃取的影响 ,优化了分析条件 ;该法在0.05～10mg·L -1范围内有良好的线性范围和重复性 ,符合生产控制的要求     

N-乙基咔唑的绿色高效合成

以咔唑为原料,碳酸二乙酯为烷基化试剂,碳酸铯和三乙基苄基氯化铵为共催化剂,经烷基化反应绿色合成了N-乙基咔唑,其结构经¹H NMR和HR-ESI-MS确证。在最佳反应条件［咔唑200 mmol,碳酸二乙酯1.2 eq.,碳酸铯（0.05 eq.）和三乙基苄基氯化铵（0.05 eq.）为催化体系,于180 ℃反应3 h］下,产率99%。     

(4R,5R)-1,3-二氧戊环-2,2-二苯基-4,5-二-[亚甲基-N,N'-(1-甲基-4-羟基苯甲醛)]的合成及其催化性能

以L-酒石酸和二苯甲酮为原料,经酯化、缩酮、加成、消除、还原和缩合等反应合成了一种新型席夫碱类化合物——(4R,5R)-1,3-二氧戊环-2,2-二苯基-4,5-二-[亚甲基-N,N'-(1-甲基-4-羟基苯甲醛)](4),其结构经1H NMR,13C NMR和LC-MS表征。以二烷基锌对苯甲醛的不对称加成为模板反应,考察了4的不对称催化性能。实验结果表明,4对该反应具有一定的催化效果(ee值52%)。     

Stereochemical behavior of 2 J(Se,H) and 3 J(Se,H) spin‐spin coupling constants across sp3 carbons: a theoretical scrutiny

A theoretical study of geminal and vicinal ⁷⁷Se‐¹ H coupling constants in the benchmark dimethyl and diethyl selenides has been performed at the SOPPA level followed by the NJC analysis within the NBO approach to reveal their stereochemical behavior in respect with the three main structural factors, namely, (i) the dihedral angle dependences, (ii) the bond angle dependences and (iii) the lone pair effects. It has been demonstrated that both geminal and vicinal couplings provide a unique stereospecificity in respect with the orientational lone pair effect together with the geometry of a coupling pathway, which is of prime importance for the stereochemical studies of organoselenium compounds. Copyright © 2012 John Wiley & Sons, Ltd.     

Highly effective and enantioselective Phospho-Aldol reaction of diphenyl phosphite with N-alkylated isatins catalyzed by quinine

Cinchona alkaloids were first successfully reported to promote enantioselective Phospho-Aldol reaction of diphenyl phosphite to a variety of N-alkylated isatin derivatives in good to excellent yields (up to 99%) and moderate to good enantioselectivities (up to 73% ee) almost in no time.