PHOSPHORUS PENTOXIDE AS AN EFFICIENT CATALYST FOR THE TETRAHYDROPYRANYLATION OF ALCOHOLS UNDER SOLVENT-FREE CONDITIONS

A facile and efficient method for the preparation of tetrahydropyranyl ethers from alcohols is improved in solvent-free media. These reactions are catalyzed by P₂O₅ and afford various tetrahydropyranyl ethers in shorter reaction time, with good to excellent yields (75–95%) at room temperature. This method is also compatible with substrates containing acid-sensitive functional groups.     

ALANINE/CHLOROCHROMIC ACID/SILICA GEL: AN EFFICIENT AND SELECTIVE REAGENT FOR THE OXIDATION OF ORGANIC FUNCTIONAL GROUPS

Alanine/chlorochromic acid/silica gel is a new and selective reagent for the efficient oxidation of sulfides, thiols, oximes, and alcohols. Oxidation of sulfides is solvent dependent. In chloroform at room temperature sulfoxides are formed as the major products, while in carbon tetrachloride or under solvent-free conditions solfones are produced in good-to-excellent yields.     

SILICA GEL SUPPORTED JONES REAGENT (SJR): A SIMPLE,VERSATILE, AND EFFICIENT REAGENT FOR OXIDATION OF ALCOHOLS IN NON-AQUEOUS MEDIA

Oxidation of alcohols to carbonyl compounds has been carried out by utilization of Jones reagent supported on silica gel (SJR). The SJR procedure has advantages over traditional Jones oxidation procedure. This procedure is safer to carry out and simplified workup by allowing organic media.     

THE USE OF NAFION-H® AS AN EFFICIENT CATALYST FOR THE DEPROTECTION OF TRIMETHYLSILYL ETHERS TO THEIR CORRESPONDING ALCOHOLS UNDER MILD AND HETEROGENEOUS CONDITIONS

Trimethylsilyl ethers were converted to their corresponding alcohols in the presence Nafion-H® and wet SiO ₂ with good-to-excellent yields under mild and heterogeneous conditions.     

聚丙烯酸芴酯的电化学氧化交联反应及其表征

合成了侧链带有芴的聚丙烯酸芴酯(PFM),在含40%三氟化硼乙醚的二氯甲烷混合电解质溶液中,直接阳极氧化PFM获得了自支撑交联网状的聚(聚丙烯酸芴酯)(CPFM)薄膜.通过UV-Vis、FTIR和1H-NMR对CPFM结构进行了表征.荧光光谱表明得到的聚合物薄膜CPFM在415nm附近处具有强的荧光发射峰,表明聚丙烯酸结构的引入没有影响聚芴的蓝色发光性能并有利于提高聚合物薄膜的力学性能.TGA表明得到的CPFM薄膜具有良好的热稳定性。     

3,6-BIS(TRIPHENYLPHOSPHONIUM)-CYCLOHEXENE PEROXODISULFATE: A HIGHLY EFFICIENT OXIDANT FOR THE SELECTIVE OXIDATION OF BENZYLIC ALCOHOLS

The synthesis of 3,6-bis(triphenylphosphonium)cyclohexene peroxodisulfate and its application for the selective oxidation of benzylic alcohols is reported.     

PYRIDINIUM SULFONATE CHLOROCHROMATE (VI), C5H5NSO3H [CrO3Cl] (PSCC): A NEW REAGENT FOR OXIDATION OF ORGANIC SUBSTRATES

A fast, mild, and reasonable oxidizing agent, pyridinium sulfonate chlorochromate (VI), C₅H₅NSO₃H [CrO₃Cl] (PSCC) is synthesized. Its reactions with primary, secondary, benzylic, and allylic alcohols under very mild conditions give the corresponding carbonyl compounds. These are obtained with relatively short reaction times. The oxidant/substrate ratios of 1:1 are employed.     

HEXAMETHYLDISILAZANE IN THE PRESENCE OF N,N′,N″,N‴-TETRAMETHYLTETRA-2,3-PYRIDINOPORPHYRAZINATO COPPER (II) IS A NEW,MILD AND HIGHLY EFFICIENT REAGENT FOR SILYLATION OF ALCOHOLS AND PHENOLS

Alcohols and phenols are protected with hexamethyldisilazane in the presence of N,N′,N′,N?-tetramethyletra-2,3-pyridinoporphyrazinato copper (II) in good-to-excellent yields at room temperature.     

无机聚合物正极材料聚三硫代磷氮烯的制备与表征

合成了无机化合物聚三硫代磷氮烯[NPS3]n,借助红外光谱与元素分析测试确定了聚合物的重复单元结构;并通过比表面积分析、粒度测试和扫描电子显微镜观察了无机聚合物材料的微观形貌;热重分析测试表明材料在300℃以下能够稳定使用;循环伏安实验发现,作为锂二次电池正极材料使用,聚三硫代磷氮烯的电化学还原反应在2.25 V(versus Li/Li+)发生,其可逆的电化学氧化反应在2.51 V(versus Li/Li+)进行;充放电测试显示这种无机材料具有745.2 mAh.g-1的首次放电容量,与理论值(759.0 mAh.g-1)十分接近,经过60次充放电循环后放电容量保持在708.8 mAh.g-1,容量保持率95.1%,循环性能优秀.     

4，4＇－偶氮二［4－氰基戊酰（对－二甲氨基）苯胺］作为引发剂的嵌段共聚物合成

４，４＇－偶氮二［４－氰基戊酰（对－二甲氨基）苯胺］作为引发剂的嵌段共聚物合成邱醒宇，魏峰，关宏宇，平学真（辽宁大学化学系，沈阳，１１００３６）关键词４，４＇－偶氮二［４－氰基戊酰（对－二甲氨基）苯胺］，多官能团引发剂，自由基聚合７０年代以来，陆续报...     

3-[N-(4-甲基苯基)氨基羰基]-5-[4-(4-甲酸基苯甲氧基)苯亚甲基]-2,4-噻唑烷二酮的合成

以对甲苯胺和对甲基苯甲酸甲酯为起始原料,经NBS溴化、亲核取代、酸水解和Knoevenagel缩合等6步反应合成了抗细菌生物膜化合物—3-[N-(4-甲基苯基)氨基羰基]-5-[4-(4-甲酸基苯甲氧基)苯亚甲基]-2,4-噻唑烷二酮,总收率57.3％,其结构经1H NMR,ESI-MS和元素分析确证.     

2-叔丁基-4-氟-苯并氧杂卓并[3,4-b]喹啉并

以2-溴甲基-6,7-亚甲二氧基-3-喹啉酸乙酯(1) 为原料,经三步合成了2-叔丁基-4-氟-苯并氧杂卓并[3,4-b]喹啉并[9,11]二氧戊环-14(6H)-酮(4).其中,6-(2-氟-4-叔丁基-苯氧甲基)-[1,3]二氧戊环并[4,5-g]喹啉-7-羧酸是经一锅法合成的.它的分子内闭环反应是在Eaton's reagent(P2O5-CH3SO3H)的作用下,在较温和的条件下进行的.所得新化合物3和4的结构经IR、1H NMR和元素分析得以证实.     

聚N-[5-(8-羟基喹啉)甲基]苯胺/介孔五氧化二钒杂化材料的制备与表征

采用原位插层聚合法制备出层状有序的聚N-[5-(8-羟基喹啉)甲基]苯胺/介孔五氧化二钒(PNQA/Meso-V2O5)杂化材料.结果显示,PNQA插入后,Meso-V2O5的层间距由2.4nm增加到2.81nm,得到的杂化材料仍保持良好的层状结构.杂化材料的室温电导率比Meso-V2O5高出3个数量级.荧光分析表明,在乙醇介质中杂化材料的发射谱带与PNQA相比蓝移22nm,杂化材料的荧光量子产率(26%)明显高于PNQA(10%).     

聚N-甲基-N-(2-甲基丙烯酰氧乙基)-对-甲苯胺的荧光光谱及光诱导接枝丙烯腈共聚合

文献[1]报道N-甲基-N-(2-甲基丙烯酰氧乙基)苯胺(MEMA)单体,由于同一分子中含有缺电子碳碳双键和给电子发色基团(芳叔胺氮上孤对电子),因此当链节克分子浓度相等时,单体的荧光强度要比其均聚物的荧光强度低得多,归之为单体“结构自猝灭”所致。这是由于共存在单体分子中的吸电子双键基团和给电子的荧光基团在光照下于分子内或分子间产生激基复合物所致。这种现象称为“结构自猝灭现象”。聚合物无双键存在,因而其荧光强度比单体高得多。     

光敏感三臂星形聚[甲基丙烯酸2-(二甲氨基)乙酯]的合成及其光敏性能研究

以香豆素为光敏感基元,通过多步反应制备了三臂ATRP引发剂C-Br3,然后以CuBr/PMDETA为催化体系、甲基丙烯酸2-(二甲氨基)乙酯(DMAEMA)为单体,ATRP聚合法制备了三臂星形聚合物C-(PDMAEMA)3.用傅里叶变换红外光谱仪(FTIR)、紫外-可见光分光光度计(UV-Vis)和核磁共振仪(1H-NMR)等对C-Br3及聚合物进行了结构表征.研究表明,该三臂星形聚合物可在水中直接形成胶束,且该聚合物可在365和254 nm交替紫外光照下发生可逆光二聚反应.纳米粒度跟踪显示,光照前其胶束粒径为(87.7±27.8)nm、呈高斯分布;而在365和254 nm光反应后,聚合物胶束粒径大小与分布仅发生微弱变化.这可能是因为在光二聚反应前后,聚合物的双亲结构变化微弱所致.     

聚[N-(4-二甲氨联苯基)马来酰亚胺]单体的合成及其聚合

N-取代的马来酰亚胺是缺电子的负性单体[1],它很容易进行自由基聚合或共聚合[2,3],特别是能够与负性单体如丙烯腈共聚合[4].如果在缺电子的N-取代马来酰亚胺单体中引入给电子生色基团,即给电子生色基团与受电子基团于一体,能够表现出较好的光化学性能[5].本文中报道了聚[N-(4-二甲氨联苯基)马来酰亚胺]及其单体的合成,聚合物的光化学性能将在另文报道.     

SYNTHESIS AND CHARACTERIZATION OF NEWLY DESIGNED POLY[DI(ALKYL) VINYLTEREPHTHALATE]S

A series of newly designed monomers of 2-vinylterephthalates (VT) were synthesized. The monomers contain onephenylene group connected with two alkyl groups (carbon number varying from 1 to 6) via ester linkage. Their chemicalstructures were confirmed by mass spectroscopy (MS), ~1-H-NMR, and elemental analysis (EA). The corresponding polymers,poly[di(alkyl) vinylterephthalate]s (PDAVTs), were obtained using convenional free redical polymerization. The polymerswere found to be able to develop inio liquid crystalline phase when the size of the alkyl group in the side-chain increases tobe larger than the ethyl group.     

聚{N-[2-(4′-硫代乙酸苄酯基)丙酰基]-对氨基苯乙炔}的合成和热稳定性及有序纳米结构的形成

采用两性离子型的催化剂Rh+[η-C6H5(nbd)B-(C6H5)3]实现了含手征性中心和硫代乙酸酯基的苯乙炔单体的聚合,用红外光谱、核磁共振氢谱和紫外-可见吸收光谱表征了聚合物的结构,证实得到了预期产物.聚合物的重均分子量达到了73200,在氯仿、四氢呋喃、二氯甲烷等有机溶剂中有良好的溶解性能.聚合物热稳定性高,在氮气氛围下热分解温度为336℃,在900℃的高温下有31%的重量残留.用扫描电子显微镜观察发现,在浓度为5.0mg/mL的聚合物氯仿溶液形成的薄膜中有微米长度的棒状有序结构;由浓度为0.5mg/mL的聚合物氯仿稀溶液形成的薄膜表面有晶体析出.用透射电子显微镜观察聚合物在氯仿溶液中缓慢形成的微结构,发现当浓度高于1.0mg/mL时,聚合物在碳膜上形成铺展的薄膜,薄膜由纳米尺寸的丝带状结构取向排列而成;当浓度低于0.5mg/mL时,聚合物形成具有规则几何形态的微晶体.在聚合物热稳定性的显著提高和有序微结构的形成过程中,聚苯乙炔侧链中的手征性中心发挥了关键的作用.     

Poly[N-(2-aminoethyl)acrylamido] triethylammonium polyhalide derivatives: Preparation and synthetic applications

Poly[N-(2-aminoethyl)acrylamido]triethylammonium dichloroiodate, tetrachloroiodate, and dibromoiodate polyhalides were developed as a new class of solid phase organic reagents. N,N′-methylenebisacrylamide crosslinked polyacrylamide support was utilized to prepare the reagents. The utility of polyhalide reagents for the α-halogenation of carbonyl compounds and oxidation of alcohols at various reaction conditions is described. The reactivity of the polyhalide reagents increased considerably in polar solvents and the optimum temperature for conducting the reactions was 30°C. Studies on halogenation and oxidation reactions using differently crosslinked polyacrylamide-based polyhalide reagents revealed that the reactivity increased up to 10% crosslinking and decreased progressively on further increase in the degree of crosslinking. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1413–1421, 1997