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1.
脂肪族酰胺二元醇的合成与表征   总被引:3,自引:1,他引:3  
刘孝波  张军华 《合成化学》1998,6(4):339-341
以DL-乳酸、ε己内酯及乙二胺和己二胺为原料合成了四种结构的脂肪族酰胺二元醇,并用IR,^1HNMR,DSC对酰胺二元醇的结构进行了表征。  相似文献   

2.
壳聚糖负载稀土催化剂催化甲基丙烯酸甲酯聚合   总被引:5,自引:0,他引:5  
对壳聚糖负载稀土配合物(Cs.RE)与三异丁基铝,ε-己内酯(CL)催化甲基丙烯酸甲酯的聚合进行了研究,综合考察了Cs.Y-Al(i-Bu)3-CL体系催化甲基丙烯酸甲酯聚合特征,聚合动力学,聚合物的分子量和其分布,甲基丙烯酸甲酯与苯乙烯共聚合行竟聚率,推测聚合反应属于配位阴离子机理,用IR,DSC,^1HNMR和^13CNMR表征了聚甲基丙烯酸甲酯的微结构,其间同立构含量达86.4%,玻璃化转变  相似文献   

3.
双羧基封端聚己内酯的合成与表征   总被引:5,自引:0,他引:5  
在氮气氛中和丁二酸存在下,进行了ε-己内酯的开环聚合。IR, ̄1HNMR和 ̄(13)CNMR测定结果表明,聚合反应产物为双羧基封端的聚ε-己内酯。产物的分子量随二元酸用量的减少而增加,在酸/内酯摩尔比为1:14,225℃聚合3小时,产物的分子量达到最大值。  相似文献   

4.
生物降解ε—己内酯/d,l—丙交酯共聚物的合成与表征   总被引:6,自引:0,他引:6  
采用一种新型的稀土配位化合物Y(CF3COO)3/Al(i-Bu)3为催化剂,制备了不同组成的ε-己内酯/d,l-丙交酯共聚物,并用GPC、NMR和DSC表征了共聚物的结构.结果表明通过改变初始投料中两种单体的比例,可以调节共聚酯的化学结构,而共聚物的形态则受结构影响很大.  相似文献   

5.
景凤英  姜洪焱 《分析化学》1998,26(4):461-465
利用一维NMR方法研究了新型聚芳醚酮大环化合物的影响,用二维同核^1H-^1H COSY和^13C-^1H COSY实验方法以及类似物质标准谱图的比较,对一维NMR谱峰进行了归属。  相似文献   

6.
用^1H-NMR^13C-NMR和二维核共振技术研究了2,2’-二(对氨苯氧基)-1,1’-联萘的结构,并通过^1H-^1H质子同核相关及^13C-^1H异核相关谱提供的信息确定了其^1H谱和^13C谱中各谱峰的归属,为聚合物的表征提供依据。  相似文献   

7.
苯乙烯—甲基丙烯酸甲酯嵌段共聚物的合成与表征   总被引:1,自引:0,他引:1  
采用阴离子聚合技术合成了一系列苯乙烯-甲基丙烯酸甲酯的两嵌段共聚物。采用GPC、FTIR、NMR(^1H NMR,^13C NMR和固体NMR)和DMA等手段进行了表征。结果表明,所得产物为高分子量,窄分布,具有微相分离结构的两嵌段共聚物。  相似文献   

8.
含钛MCM—41分子筛的合成与表征   总被引:1,自引:1,他引:1  
水热法合成了含钛的MCM-41型超大孔分子筛,通过XRD,IR,DRSUV-VIS,^29SiMASNMR等测试,表明钛处在分子筛骨架上,同时考察了Na^+、Al^3+对TiMCM-41合成的影响以及分子筛的热稳定性、吸附量和催化活性。  相似文献   

9.
在乙腈介质中合成了苯并-12-冠-4(简称B-12-C-4)和单环己基-12-冠-4(简称Cy-12-C-4)的六种希土配合物:RE(NO3)3·B-12-C-4(RE=Pr,Gd,Yb,Lu),RE(NO3)3·Cy-12-C-4(RE=La,Lu)。研究了它们的IR及^1HNMR性质,并测定了四种单晶的结构,用INDO法计算了Lu(NO3)3·B-12-C-4,Lu(NO3)3·Cy-12-C  相似文献   

10.
用一维^1H NMR、^13C NMR方法研究了2,2’-(3,4-四酸二酐)二苯甲酰氧基-1,1‘-联萘的并通过二维^1H-^1H同核相关,^13C-^1H异核相关及^13C-^1H异核远程相关谱进一步地确定其^1H谱和^13C谱中各谱峰的归属。为同类化合物的表征提供了依据。  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.
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   

14.
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   

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.
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   

19.
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   

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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