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1.
金表面偶氮苯自组装膜的光电化学响应   总被引:2,自引:2,他引:2  
金表面偶氮苯自组装膜的光电化学响应王永强,王健,于化忠,蔡生民,刘忠范(北京大学化学与分子工程学院智能材料研究中心,北京,100871)关键词偶氮苯,自组装膜,光致异构化,电化学偶氮苯基团特征的光致异构化及电化学响应在分子开关器件和超高密度信息存储等...  相似文献   

2.
富勒烯四甲氧基衍生物的合成与表征甘良兵,周胜,姜剑峰,黄春辉(北京大学化学与分子工程学院,北京,100871)武轶,吕木坚,潘景歧(北京微量化学研究所)(北京大学分析测试中心)关键词C_60衍生物,甲氧基,四氮杂环十二烷富勒烯化学是目前人们研究的热门...  相似文献   

3.
甲基丙烯酸(3 三甲氧基硅)丙酯 马来酸二丁基锡共聚物/二氧化硅杂化材料的制备周文董建华丘坤元(北京大学化学与分子工程学院高分子科学与工程系,100871北京)WeiYen(危岩)(DepartmentofChemistry,Drexel...  相似文献   

4.
N,N'-二(乙酰芳香环)-穴醚[2,2]的合成余江,许振华,徐光宪(北京大学化学与分子工程学院,稀土材料化学及应用国家重点实验室,北京,100871)关键词大环,穴醚[2,2],HTTA穴醚(Cryptand)是含有O及N和S等杂原子的多聚大环化合...  相似文献   

5.
强绿荧光铽-异丁酰基吡唑啉酮配合物的合成、荧光性能及LB膜李琴,周德建,姚光庆,黄春辉S.UmetaniM,Matsui(北京大学稀土材料化学及应用国家重点实验室,北京,100871)(日本京都大学化学研究所)关键词铽,1-苯基-3-甲基-4-异丁酰...  相似文献   

6.
两种C_(60)-甘氨酸酯衍生物的室温荧光光谱周德建,甘良兵,谭海松,骆初平,姚光庆,黄春辉(北京大学稀土材料化学及应用国家重点实验室,北京,100871)关键词C_(60)-甘氨酸酯衍生物,浓度猝灭,荧光寿命C60在低温或室温及在紫外或可见光的激发下...  相似文献   

7.
生理条件下稀土及钙、锌离子与L-羟脯氨酸配位作用的研究*高峰**牛春吉孟淑兰倪嘉缵(中国科学院长春应用化学研究所稀土化学和物理开放实验室长春130022)金天柱王瑞瑶王祥云(北京大学稀土材料化学和应用国家重点实验室北京100871)关键词稀土钙锌L-...  相似文献   

8.
稀土氮杂大环多羧酸配合物Na[Ln(DOTMA)(H_2O)]·2H_2O的合成与表征陈德福,金天柱(北京大学稀土材料化学及应用国家重点实验室,北京,100871)关键词稀土,氮杂大环多羧酸,配合物核磁共振成像技术已成为肿瘤和其它病变组织的临床诊断及生...  相似文献   

9.
可聚合脂质体的研究Ⅳ含丙烯酰基的类脂分子及其与亲水性丙烯酰单体的共聚物金威曲青蓝李子臣李福绵(北京大学化学与分子工程学院北京100871)关键词可聚合类脂分子,共聚合,自组织,脂质体脂质体因其优异的生物相容性做为药物释放材料而备受瞩目.一般说来,...  相似文献   

10.
第4届中国多肽国际学术会议在成都召开叶蕴华徐筱杰(北京大学化学与分子工程学院北京100871)经国家教委批准,由北京大学主办,四川大学协办的第4届中国多肽国际学术会议(In-ternationalChinesePeptideSymposium1996...  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

14.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

18.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

19.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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