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1.
海绵Spongia sp.化学成分的研究(Ⅰ)   总被引:2,自引:0,他引:2  
应用气相色谱-质谱联用技术从海绵Spongia sp. 中分离鉴定出4个化学成分: 1-氯-2,2-二对氯苯基乙烯(DDMU,Ⅰ)、 1,1-二氯-2,2-二对氯苯基乙烯(DDE,Ⅱ)、 1,1-二氯-2,2-二对氯苯乙烷(DDD, Ⅲ)和角鲨烯(Ⅳ)。前3个化合物是首次从Spongia属海绵中分离得到。  相似文献   

2.
从1,1′-联萘-2,2′-二胺出发,合成了旋光性二酐单体及相应的外消旋体:(S)-,(R)-和(±)-2,2′-(3,3′,4,4′-四酸二酐)二苯甲酰胺-1,1′-联萘.二酐与二胺单体通过溶液缩聚反应制得一系列旋光性聚酰胺酰亚胺.聚合物具有较好的热稳定性、旋光稳定性、良好的溶解性以及独特的光学性质  相似文献   

3.
海绵Phyllospongia sp.中两个新的Scalarane型二倍半萜   总被引:2,自引:1,他引:2  
海绵Phyllospongiasp.中两个新的Scalarane型二倍半萜万一千,苏镜娱,曾陇梅,王明焱(中山大学化学系,广州,510275)关键词海绵,二倍半萜,分离,结构鉴定Phyllospongia属含有丰富二倍半萜的海绵体[1~7],从这种海...  相似文献   

4.
二安替比林基氯代苯基甲烷与钒(Ⅴ)显色反应的研究   总被引:15,自引:1,他引:15  
合成了二安替比林-邻氯苯基甲烷(DAoCM),二安替比林-间氯苯基甲烷(DAmCM),二安替比林-2,4-二氯苯基甲烷(DADCM)三个新试剂。研究了它们与钒(Ⅴ)的显色反应,得到了一些取代基位置对试剂性能影响的规律。建立了三个光度法测定微量钒的新方法。  相似文献   

5.
甲基、磺酸基取代的9,9'-双吖啶衍生物的化学发光研究   总被引:4,自引:0,他引:4  
庄惠生  陈国南  黄金陵 《分析化学》1999,27(10):1146-1150
研究了10,10’-二甲基-9,9-双吖啶(DMBA),2,2‘-二磺酸基-9,9-双吖啶二硝酸盐(DSBADN),10,10’-二甲基-2,2‘-二磺酸基-9,9’-双吖啶(DMDSBA),及10,10‘-二甲基-9,9’-双吖啶二硝酸盐9DMBADN,谷称光泽精)等4种9、9‘-双吖啶衍生物的化学发性质,发现10,10’-二 磺酸基-9,9‘-双吖啶的化学发光强度是光泽精的22倍,是迄今为止发  相似文献   

6.
含联萘基团施光性聚酰亚胺的合成与性质   总被引:1,自引:1,他引:0  
从1,1′-联萘-2,2′-二胺出发,合成了旋光性二酐单体及相应的外消旋体:(S)-,(R)-和(±)-2,2′-(3,3′,4,4′-四酸二酐)二苯甲酰胺01,1′-联萘。二酐与一胺单体通过溶液缩聚反应制得一系列旋光性聚酰胺亚胺。聚合物具有较好的热稳定性、旋光稳定性、良好性的溶解性以及独特的关学性质。  相似文献   

7.
对映体的气相色谱分析Ⅱ.手性芳香二级醇的分离测定   总被引:2,自引:0,他引:2  
吴兰均  李智  宓爱巧  蒋耀忠 《色谱》1996,14(2):81-85
在手性毛细管柱Chirasil-L-Val(玻璃柱)、CYDEX-β-全甲基化β-环糊精(交联弹性石英柱)上考察了苯乙醇腈、1-苯基-1-乙醇、1-苯基-1-丙醇、1-苯基-2,2-二甲基-1-丙醇、1-(4-氯苯基)-1-乙醇芳香二级醇对映体分离的色谱行为。并测定了一系列不对称合成实际样品中对映体过量值(即e.e.值)。  相似文献   

8.
反相离子对高效液相色谱法分离和测定铝、镓和铟   总被引:7,自引:2,他引:7  
以芪-4,4‘-双(1-偶氮)-3,4-二羟基苯-2,2’-二磺酸铵(芪唑)为柱前衍生试剂,采用反相离子对高效液相色谱法分离和测定铝,镓和铟。在spherex C18柱上,用浓度为12mmol/L的SDS,浓度为20mmol/l pH3.5的AHc-NaAc的甲醇-水溶液作流动相,检测波长为506nm。  相似文献   

9.
配体1,1’-双(四甲基环戊二烯基)二茂铁1,1’-Fc(Me4Cp)2(Ⅰ)与五羰基铁在二甲苯中回流反应,得二藏铁桥连双(四甲基环戊二烯基)四羰基二铁1,1’-Fc「(Me4Cp)Fe(CO)(μ-CO)」2(1).化合物1在氯仿中与单质碘反应,Fe-Fe键断裂,生成二茂铁桥边双铁碘化合物1,1’-Fc「(Me4Cp)Fe(CO)2I」2(2).配体Ⅰ与正丁基锂作用生成二茂铁桥边双(四甲基环戊二  相似文献   

10.
利用高压差示扫描量热法(PDSC)研究了二烷基二硫代氨基甲酸锌(VAZ)、2,2′-亚甲基双(4-甲基-6特丁基苯酚)(2246)、苯江三唑(BTZ)和二烷基对苯二胺(DBA)4种抗氧添加剂对菜子油氧化稳定性的影响,得到了它们抗氧化作用的大小顺序。别外,根据队仑尼乌斯公式计算了不同油样氧化反应的活化能,证明了PDSC是一种快速简便评价基础油氧化稳定性的方法,适用于抗氧添加剂配方的设计工作。  相似文献   

11.
Two iron(I) porphyrins were electrogenerated and then utilized as catalysts for the reductive dechlorination of 1,1‐bis(4‐chlorophenyl)‐2,2,2‐trichloroethane (DDT) in N,N′‐dimethylformamide. No reaction is observed between DDT and the Fe(III) or Fe(II) forms of the porphyrin, but the electrogenerated Fe(I) porphyrin efficiently catalyzes the electroreduction of DDT to give (1,1‐bis(4‐chlorophenyl)‐2,2‐dichloroethane) DDD, (1,1‐bis(4‐chlorophenyl)‐2,2‐dichloroethylene) DDE and (1,1‐bis(4‐chlorophenyl)‐2‐dichloroethane) DDMU as determined by GC‐MS analysis. The reductive dechlorination was monitored by electrochemistry, controlled potential electrolysis and spectroelectrochemistry and a mechanism for the reaction involving the reduced porphyrins and DDT is proposed. Comparisons are also made between the catalytic properties of metalloporphyrins containing iron, cobalt and manganese central metal ions under the same solution conditions.  相似文献   

12.
《Electroanalysis》2006,18(4):417-422
In dimethylformamide containing tetramethylammonium tetrafluoroborate, cyclic voltammograms for reduction of 4,4′‐(2,2,2‐trichloroethane‐1,1‐diyl)bis(chlorobenzene) (DDT) at a glassy carbon cathode exhibit five waves, whereas three waves are observed for the reduction of 4,4′‐(2,2‐dichloroethane‐1,1‐diyl)bis(chlorobenzene) (DDD). Bulk electrolyses of DDT and DDD afford 4,4′‐(ethene‐1,1‐diyl)bis(chlorobenzene) (DDNU) as principal product (67–94%), together with 4,4′‐(2‐chloroethene‐1,1‐diyl)bis(chlorobenzene) (DDMU), 1‐chloro‐4‐styrylbenzene, and traces of both 1,1‐diphenylethane and 4,4′‐(ethane‐1,1‐diyl)bis(chlorobenzene) (DDO). For electrolyses of DDT and DDD, the coulometric n values are essentially 4 and 2, respectively. When DDT is reduced in the presence of a large excess of D2O, the resulting DDNU and DDMU are almost fully deuterated, indicating that reductive cleavage of the carbon–chlorine bonds of DDT is a two‐electron process that involves carbanion intermediates. A mechanistic scheme is proposed to account for the formation of the various products.  相似文献   

13.
The controlled-potential electrolysis of 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane (DDT) was carried out at -1.4 V vs. Ag-AgCl in the presence of a hydrophobic vitamin B12, heptamethyl cobyrinate perchlorate. DDT was dechlorinated to form 1,1-bis(4-chlorophenyl)-2,2-dichloroethane (DDD), 1,1-bis(4-chlorophenyl)-2,2-dichloroethylene (DDE), 1-chloro-2,2-bis(4-chlorophenyl)ethylene (DDMU) and 1,1,4,4-tetrakis(4-chlorophenyl)-2,3-dichloro-2-butene (TTDB)(E/Z), and quantitative recovery of the catalyst after the electrolysis was confirmed by electronic spectroscopy. A photo-sensitive intermediate having a cobalt-carbon bond formed during the electrolysis was characterized by electronic spectroscopy. A mechanism for the formation of various dechlorinated products was investigated by using deuterium solvents and various spectroscopic measurements such as UV-VIS and the EPR spin-trapping technique.  相似文献   

14.
建立了用离子抑制色谱法分析二(2,2,6,6-四甲基-4-哌啶基)马来酸酯合成反应液的方法。平均回收率为98.8%,相对标准偏差为0.56%,测量的平均相对偏差不大于5.0%。方法简单、快速,可用于工艺条件的选择和质量检测。  相似文献   

15.
通过双吡唑甲基锂(LiCHPz2)与有机锡卤化物(R3SnX)的反应合成了一系列有机锡修饰的双吡唑甲烷配体(R3SnCHPz2).由于锡上取代基的不同,这些配体与W(CO)5THF反应时表现出了不同的反应方式.三芳基锡修饰的双吡唑甲烷与W(CO)5THF反应发生Sn-C(sp3)键对W(0)中心的氧化加成;而三苄基锡修饰的双吡唑甲烷与其反应时仅给出羰基取代产物[Bz3SnCHPz2W(CO)4].另外,二苯基苄基锡以及三(2-苯基-2-甲基丙基)锡修饰的双吡唑甲烷配体类似的反应导致配体的分解,产生单吡唑配体取代的羰基钨衍生物[W(CO)5PzH]以及脱有机锡的双吡唑甲烷四羰基钨衍生物[CH2Pz2W(CO)4].  相似文献   

16.
The condensation reaction of 2,2′‐diamino‐4,4′‐dimethyl‐6,6'‐dibromo‐1,1′‐biphenyl with 2‐hydroxybenzaldehyde as well as 5‐methoxy‐, 4‐methoxy‐, and 3‐methoxy‐2‐hydroxybenzaldehyde yields 2,2′‐bis(salicylideneamino)‐4,4′‐dimethyl‐6,6′‐dibromo‐1,1′‐biphenyl ( 1a ) as well as the 5‐, 4‐, and 3‐methoxy‐substituted derivatives 1b , 1c , and 1d , respectively. Deprotonation of substituted 2,2′‐bis(salicylideneamino)‐4,4′‐dimethyl‐1,1′‐biphenyls with diethylzinc yields the corresponding substituted zinc 2,2′‐bis(2‐oxidobenzylideneamino)‐4,4′‐dimethyl‐1,1′‐biphenyls ( 2 ) or zinc 2,2′‐bis(2‐oxidobenzylideneamino)‐4,4′‐dimethyl‐6,6′‐dibromo‐1,1′‐biphenyls ( 3 ). Recrystallization from a mixture of CH2Cl2 and methanol can lead to the formation of methanol adducts. The methanol ligands can either bind as Lewis base to the central zinc atom or as Lewis acid via a weak O–H ··· O hydrogen bridge to a phenoxide moiety. Methanol‐free complexes precipitate as dimers with central Zn2O2 rings.  相似文献   

17.
Pressurised liquid extraction (PLE) was used to extract DDT [1,1,1,-trichloro-2,2-bis(p-chlorophenyl)ethane] and its metabolites, DDD [1,1-dichloro-2,2-bis(p-chlorophenyl)ethane] and DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene] from an aged, contaminated soil. Using three sequential static phases, PLE removed an equivalent quantity of DDT and its metabolites as Soxhlet extraction, in less time and with less solvent. Recovery was almost quantitative, implying appropriate sample work-up and manipulation.  相似文献   

18.
分别以Fe(Cl O4)3、FeCl3、Fe2(SO4)3作为氧化剂,对3′,4′-乙撑二氧-2,2′∶5′,2″-三噻吩(TET)进行了化学氧化聚合,并研究了聚合条件对聚合物结构和电化学性能的影响。利用红外光谱、紫外光谱、X射线衍射对聚合物进行了表征,采用循环伏安、恒电流充放电等电化学方法研究了聚合物的电化学性能。结果表明:当TET与Fe(Cl O4)3的摩尔比为1∶4,反应温度为18℃,反应时间为12 h时,聚3′,4′-乙撑二氧-2,2′∶5′,2″-三噻吩(PTET)具有更好的共轭结构和电化学性能,导电率可达1.47 S/m,比电容可达133 F/g。  相似文献   

19.
The reactions of dehydrochlorination of 1,1‐trichloro‐2,2‐bis(p‐chlorophenyl)ethane, DDT, and 1,1‐dichloro‐2,2‐bis(p‐chlorophenyl)ethane, DDD, with hydroxide ions were studied in various TTAB–alcohol (TTAB = tetradecyltrimethylammonium bromide) aqueous micellar solutions as a function of alcohol content. The alcohols used were heptanol, hexanol, pentanol, butanol, isobutanol, tert butanol, propanol and isopropanol. Kinetic data show that the dissociation degree of the micelles is the main factor controlling reactivity in all the TTAB–alcohol micellar solutions. This fact permits the development of a kinetic method in order to estimate the dissociation degree of the micellar aggregates present in the alcohol–TTAB aqueous micellar solutions. © 2000 John Wiley & Sons, Inc. Int J Chem Kinet 32: 204–209, 2000  相似文献   

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