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1.
研究了在35±0.1℃、离子强度0.5mol/L(KCl)条件下,甲酸根、乙酸根、丙酸根和丁酸根分别催化Cu(Ⅱ)离子与四溴化间-四(N-乙酸甲酯基-3-吡啶基)卟啉(H2TB-N-ACMSpyPBr4)的反应动力学及其机理,该类反应对卟啉和Cu(Ⅱ)离子均为一级反应,反应动力学方程为:d[Cup4+]/dt=k{(1.0+b[A-])/(1.0+K3,4·[H+]2)}[Cu2+][p]T,在甲酸-甲酸根缓冲体系中,k=2.98mol-1dm3·sec-1,b=154×102mol-2,dm6·sec-1,K3,4=6.928×103;在乙酸-乙酸根缓冲体系中,k=3.42mol-1·dm3·sec-1,b=2.29×103mol-2·dm6·sec-1,K3,4=6.928×103;在丙酸-丙酸根缓冲体系中,k=3.00mol-1·dm3·sec-1,b=5.90×102mol-2·dm6·sec-1,K3,4=7.007×103;在丁酸-丁酸根缓冲体系中,k=3.14mol-1·dm3·sec-1,b=3.75×102mol-2·dm6·sec-1,K3,4=6.921×103;讨论了有机酸根的碱性与  相似文献   

2.
研究了在35±0.1℃、离子强度0.5mol/L(KCl)条件下,甲酸根、乙酸根、丙酸根和丁酸根分别催化Cu(Ⅱ)离子与四溴化间-四(N-乙酸甲酯基-3-吡啶基)卟啉(H2Tβ-N-ACMspyPBr4)的反应动力学及其机理,该类反应对卟啉和Cu(Ⅱ)离子均为一级反应,反应动力学方程为:d[CuP^4+]/dt=k{1.0+b[A^-])/(1.0+K3,4.[H^+]^2}[Cu^2+][P]T  相似文献   

3.
利用小分子meso-四(α,α,α,α-O-苯乙酰苯)卟啉作为全抗原免疫小鼠,通过细胞融合等技术制备了单克隆抗体(McAb)1F2,利用高效液相色谱(HPLC)、基质辅助激光解吸飞行时间质谱(MALDI/TOFMS)证明纯化得到的单抗是很纯的.McAb1F2的保留时间是2.63 min,亚型为IgG2a,相对分子量为156 678.8.McAb 1F2-卟啉复合物形成时,卟啉Soret带最大吸收峰从408nm红移到416nm,并有增色效应,说明McAb1F2-卟啉是刚性且紧密结合.抗体酶稳定性很高,但比活力只有4.687 5 U/mg,为天然酶HRP的1.899%.抗体酶的Km=20.29 mmol/L,kcat=396.82 min-1,kcat/Km=1.955 7×104L·mol-1·min-1.  相似文献   

4.
研究了在35±0.1℃、离子强度0.5mol/L(KCl)下,乳酸根催化Cu^2+离子嵌入溴化间-四(N-乙酸甲酯基-3-吡啶基)卟啉和溴化间-四(N-氰乙基-3-吡啶基)卟啉的反应动力学。根据催化剂浓度、溶液的pH值与反应速率间的关系。得到Cu^2+离子嵌入该类卟啉的反应动力学方程。。实验结果表明,该类反应遵循负离子催化卟啉变机理,变形的卟啉及其与乳酸根离子的缔合物为可能的活性中间体。  相似文献   

5.
赵军  杨世琰 《合成化学》1996,4(3):257-260
光学活性二醇(1R,2R)-(+)-1,2-二苯基-1,2-乙二醇(Ⅲa)和(2R,3R)-(-)-1,1,4,4-四苯基-2,3-(缩丙酮)-1,4-丁二醇(Ⅲb)分别修饰Ti(OPri)3Cl,再与甲基锂和乙基锂进行烷基化,制备出新的手性有机钛试剂Ⅱa和Ⅱb,然后与苯甲醛进行加成,所得1-苯基乙醇(Ⅳa)和1-苯基丙醇(Ⅳb)的光学收率分别为25~65%e.e.和10~20%e.e.。简单讨论了C2-对称型二醇对立体选择性及反应条件的影响  相似文献   

6.
对-叔丁基杯[4]芳烃在环己烷中的激光光解研究*袁立华1姚思德2庄志豪1林念芸2(1.四川联合大学化学系成都610064)(2.中国科学院上海原子核研究所辐射化学实验室上海201800)关键词对-叔丁基杯[4]芳烃激光光解三线态中图分类号O621.2...  相似文献   

7.
研究了1-芳基-4-乙氧羰基-5-氨基-1,2,3-连三唑(1)同甲酰胺、异氰酸磺酰氯以及内酰亚胺醚等的反应,制得5-H-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4-酮(2a-c)、5-N-甲基-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4-酮(3a-c)、1-芳基-4-乙氧羰基-5-脲基-1,2,3-连三唑(4a,b)、5-H-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4,6-二酮(5_(a,b))、1-苯基-1,2,3-连三唑[4,5-e]哌啶[1,2-b]嘧啶-4-酮(6a)、1-苯基-1,2,3-连三唑[4,5-e]氢化吖辛因[1,2-b]嘧啶-4-酮(7a),并经元素分析、红外、核磁共振以及质谱等方法确认了它们的结构,初步筛选了其代表特的生物活性.  相似文献   

8.
用X-射线测定了meso-5,10,15,20-四(3,4,5-三甲氧基苯基)卟啉的溶剂(正庚烷)合物(TTOMPP·2C_7H_(16))的晶体结构。实验表明,该化合物(C_(70)H_(86)N_4O_(12))的晶体属三斜晶系,空间群P1,a=8.749(6),b=15.129(6),c=16.449(3),a=60.07(3),β=70.64(4),γ=81.70(5),V=1779.6,M_r=1175.49,Z=1,D_c=1.097g/cm ̄3,μ=0.697cm ̄(-1),F(000)=630。讨论了卟啉环上取代基的电子和立体效应及卟啉与铁(Ⅲ)离子配位后铁(Ⅲ)离于对卟啉结构参数的影响。  相似文献   

9.
β,β-1,5-亚丙二硫基-α,β-不饱和酮2b和2-甲基烯丙基氯化镁加成可得醇3b.在BF3·Et2O催化下,3b经分子内环合芳构化生成芳硫醚5b.2和烯丙基溴化镁反应得醇4,4在BF3·Et2O催化下经β-消除脱水生成共轭多烯类化合物6.二硫缩醛基以环和非环结构及环的大小对2与烯丙基Grignard试剂加成物在酸催化下的反应取向有重要影响。  相似文献   

10.
本文研究了新水溶剂卟啉试剂5,10,15,20-四(3-溴-4-磺酸苯基)卟啉(T(3-BrP)PS4)与铜的显色反应,在pH3,铜与5,10,15,20-四(3-溴-4-磺酸苯基)卟啉形成1:1的稳定配合物,此配合物的最大吸收波长位于412.8nm摩尔吸光系数为2.61×10^5L.mol^-1.cm^-1。铜量在0~3.0μg/25mL范围内符合比尔定律,工作曲线回归方程为y= 0.00943  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.
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   

14.
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   

15.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

16.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

17.
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   

18.
Siqi Li  Xingpeng Chen  Jiaxi Xu 《Tetrahedron》2018,74(14):1613-1620
Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular SN2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.  相似文献   

19.
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   

20.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

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