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1.
本文讨论了Roussin黑盐的形成机理和“G”系模型物结构及其固氮活性成因的化学和量子化学研究结果。并由此提出了过渡金属类立方烷型簇合物合成中的“活性元件组装”设想;即过渡金属原子簇,特别是含μ2和μ3桥的类立方烷簇,可能由构成该原子簇的基本结构“元件”在一定活化条件下组装而成。考察了现有的Fe-S,Mo-S,Mo-Fe-S以及一些M-M′-X构型相类似的类立方烷簇合物,如[Fe_4S_4(SR)_4]~(2-),[MoFe_3S_4(SR)_n]~(m-),[VFe_3S_4Cl_3(DMF)3]单类立方烷簇,[Mo_2Fe_6S_9(SR)_8]~(8-),[Mo_2Fe_6S_8(SR)_9]~(3-),[Mo_2Fe_7S_8(SR)_(12)]~(3-,4-)桥联双立方烷簇以及(MeZn)_6Zn(OMe)_8孪合双立方烷簇的自兜合成反应,发现尽管它们似乎都是由简单的无机盐和有机配体“自兜”而成,然而它们都不能不经过某些“元件组装”的过程。提出了它们的可能的“元件组装”途径。此外还讨论了“元件组装在其他合成Mo、Fe、S类立方烷簇的反应中的存在。最后还进一步探讨了其他类型簇合物合成反应情况,表明“元件组装”设想是可能推广到类立方烷型簇以外的其他一些原子簇的合成的。  相似文献   

2.
本文通过MoFe_3S_4类立方烷簇合物的合成途径(自兜反应及链状簇转化反应)的研究,归纳出合成过程特点,讨论了计量化学关系、配体氧化还原能力和配体结构对类立方烷原子簇结构及核心氧化态的影响,指出自兜反应可能由含结构单元的链状中间物的组合过程而进行。  相似文献   

3.
双-2-萘甲酸多亚甲基二醇酯(N-Mn-N,n=2,3,4,5)在环己烷中进行光二聚反应的效率和产物的结构明显受链节长度的影响.N-M3-N生成反式-头头和顺式-头头两种结构的类立方烷,而N-M4-N和N-M5-N高产率、高区域选择性地生成反式-头头结构的类立方烷.更有意义的是,我们利用高效液相色谱成功拆分了反式-头头结构的分子内光二聚产物.  相似文献   

4.
FOX-7的合成和反应机理研究   总被引:11,自引:0,他引:11  
以2-甲基咪唑为原料合成出1,1-二氨基-2,2-二硝基乙烯(FOX-7)并进行了结构表征,从中间体过滤母液中分离出副产物2-甲基-4(5)-硝基咪唑和仲班酸.直接合成的2-甲基-4(5)-硝基咪唑和仲班酸,最佳收率分别为67.3%和63.3%.首次提出了一个较为完整而详细的合成FOX-7的反应机理,硝基重排成亚硝酸酯是反应的关键步骤.FOX-7主要是通过2-甲基咪唑→2-甲基-4(5)-二氢-5-咪唑啉酮→2-(二硝基亚甲基)-5,5-二硝基-4-咪唑烷二酮→2-(二硝基亚甲基)-4,5-咪唑烷二酮→FOX-7步骤形成.论述了各中间体形成的详细过程并进行了证明,应用该机理解释了硝化过程中主产物和副产物的变化规律.  相似文献   

5.
在醋酸铜催化作用下,以抗坏血酸钠为还原剂,以醛、2,2-二甲基-1,3-二噁烷-4,6-二酮和苯乙炔为原料,通过包含Knoevenagel缩合与Conjugate加成反应的多组分反应,有效地合成了10种5-(1-苯基-3-苯基丙基-2-炔基)-2,2-二甲基-1,3-二噁烷-4,6-二酮衍生物.该工艺具有收率高(63%~86%)、反应温和、操作简单及环境友好等优点,为合成5-(3-苯基-1-苯基丙基-2-炔基)-2,2-二甲基-1,3-二噁烷-4,6-二酮衍生物提供了一种有效的方法.  相似文献   

6.
在生物介质葡萄糖酸水溶液中,以芳香醛和2,2-二甲基-1,3-二噁烷-4,6-二酮为原料,40℃合成了6种5,5-(苯基亚甲基)双(2,2-二甲基-1,3-二噁烷-4,6-二酮)衍生物.该反应具有收率高(81%~92%)、反应温和、操作简单及环境友好等优点.此外,葡萄糖酸溶液还可重复使用.  相似文献   

7.
丙二酸甲(乙)烷酯类是一些药物和天然产物合成的中间体,一般由丙二酸二甲(乙)酯经部分水解得到丙二酸单甲(乙)酯钠盐,再通过酸化、酰氯化和酯化反应制得[1],该方法路线较长、酰氯化反应会产生有毒尾气。羧酸(包括烷酸和芳酸)酯可由其盐和卤代烃直接反应制得[2-4],而且可利用无溶剂相转移催化的条件进一步加速反应和提高产率。微波技术用于有机合成[5-7]具有操作简便、产率高和速度快等优点。我们参考文献[2-4]方法,应用微波技术合成了标题化合物。1 实验部分1 1 仪器BrukerDPX 300FT NMR型核磁光谱仪,TMS为内标;IR…  相似文献   

8.
以芳香醛和2,2-亚丁基-1,3-二噁烷-4,6-二酮为原料,以水为反应介质,无需外加催化剂,通过Knoevenagel缩合与Michael加成的串联反应简单有效地合成了5,5-(苯基亚甲基)双(2,2-亚丁基-1,3-二噁烷-4,6-二酮)衍生物.一系列取代芳香醛被考察,发现该反应具有收率高(63%~83%)、反应温和、操作简单及环境友好等优点.  相似文献   

9.
以嘧啶胺、芳醛和硫代水杨酸为原料,利用三组分一锅法,微波辐射10 min,合成了系列含新型二芳基苯并噻嗪烷-4-酮衍生物,反应具有时间短、操作简便等优点.目标化合物结构通过IR、NMR、MS及元素分析等确定.2-(2,6-二氯苯基)-3-(4,6-二甲基嘧啶-2-基)-2H-1,3-苯并噻嗪烷-4-酮(10c)表现出良好的HIV-RT抑制活性,IC50值为8.38μmol·L-1,其余化合物则具有中等的酶抑制活性.  相似文献   

10.
立方烷结构的过渡金属簇具有特殊的磁性,催化活性和稳定性等而备受关注[1]。超过7核的立方烷类铜簇化合物已知的甚少,典型的代表有羟基氧桥连的共角二联立方烷类七核铜簇[Cu7(OH)6Cl2(pn)(H2O)2](C(CN)3)4Cl2(pn=1,3 di aminopropane)[2]和[Cu7(bpym)6(OH)8(H2O)2](NO3)6·H2O(bpym=2,2 bipyrimidine)[3]以及烷氧桥连的双立方烷类八核铜簇[Cu8L8(O2CMe)4][ClO4]4(L=di 2 pyridyldetone)[4]等。我们采用水热方法合成了多立方烷类三维的具有开放式骨架的[Cu3Cl6]∞铜簇合物,并用X射线晶体衍射进行了结构表征。1 实验部分1 1…  相似文献   

11.
A capillary liquid chromatography (cLC) method with gradient elution has been used to determine chlorophenoxy acid herbicides: 2,4-dichlorophenoxyacetic acid, 4-chloro-2-methylphenoxyacetic acid, 2-(2,4-dichlorophenoxy)propanoic acid, 2-(4-chloro-2-methylphenoxy)propanoic acid, 4-(2,4-dichlorophenoxy)butanoic acid, 4-(4-chloro-2-methylphenoxy)butanoic acid, 2-(2,4,5-trichlorophenoxy)propanoic acid, 2,4-dichlorophenoxyacetic-1-methyl ester and 2,4-dichlorophenoxyacetic-1-butyl ester in spiked apple juice samples with amounts between 0.025 and 0.150 mg kg(-1) of each herbicide. Clean-up and preconcentration of acid and esters were carried out in an Oasis MCX polymer. Detection limits obtained by cLC, between 0.005 and 0.018 mg kg(-1), allowed the determination of chlorophenoxy acids and their esters in apple juice samples around the levels permitted by the European Regulations, with recoveries in the range 84-99% and RSDs between 1 and 4%.  相似文献   

12.
Methyl 3,4,6-trioxoalkanoates (3,4-dihydroxy-6-oxo-2,4-alkadienoates) reacted with 2,4-dinitrophenylhydrazine to give methyl 3,6-bis[(2,4-dinitrophenyl)hydrazinylidene]-4-oxoalkanoates or methyl {5-alkyl-2-hydroxy-1-(2,4-dinitroanilino)-3-oxo-2,3-dihydro-1H-pyrrol-2-yl }acetates. Alkyl 3,6-bis[(2,4-dinitrophenyl) hydrazinylidene]-4-oxoalkanoates were also synthesized by reaction of disodium 1-alkoxy-1,6-dioxoalka-2,4-diene-3,4-diolates with 2,4-dinitrophenylhydrazine.  相似文献   

13.
1,1-Diakyl(aryl)4-alkyl(aryl)-4-methoxy-1-germacyclohexa-2,5-dienes undergo ether cleavage with sodium in n-pentane or liquid ammonia. Hydrolysis of the resulting sodium salts yields the 1,1-dialkyl(aryl)-4-alkyl(aryl)-1-germacyclohexa-2,4-dienes. Reduction of 1-chloro-4-methoxy-1-germacyclohexa-2,5-dienes with LiAlH4 can be directed to give the 1H-1-germacyclohexa-2,4-dienes with ether cleavage.The 1H-1-germacyclohexadienes are chlorinated by PCl5 and brominated by N-bromosuccinimide to the 1-chloro- or 1-bromo-1-germacyclohexa-2,4-dienes, respectively. 1,1-Diethyl-4-phenyl-4-methoxy-1-germacyclohexa-2,5-diene reacts with PCl3 with ether cleavage and formation of the 6-chloro-1-germacyclohexa-2,4-diene. Ether cleavage is also possible with BCl3, the 1-phenyl-1-chloro-4R-4-methoxy-1-germacyclohexa-2,5-dienes are transformed into the 1-phenyl-1,6-dichloro-4R-1-germacyclohexa-2,4-dienes.The Fe(CO)3 complexes of 1,1-dialkyl(aryl)-1-germacyclohexa-2,4-dienes were synthesized.  相似文献   

14.
采用水热法合成出一种含一价铜配合物的新型双金属钼氧簇合物[5-(4-Br-Ph)-2,4'-Hbpy]2[Cu(5-(4-Br-Ph)-2,4'-bpy)2]2[Mo8O26],并通过X射线单晶结构分析、红外光谱分析、元素分析以及X射线粉末衍射分析对该化合物的结构进行了表征.结果表明,该化合物属单斜晶系,P21/c空间群,晶胞参数a=1.4411(3)nm,b=1.3924(3)nm,c=2.5183(5)nm,β=99.06(3)°,V=4.990(17)nm3,Z=2;该化合物是由一价铜配合物{Cu(5-(4-Br-Ph)-2,4'-bpy)2}+与{β-Mo8O26}4-簇通过共价配位键连接形成的新型多金属钼酸盐,其中游离的质子化配体作为抗衡阳离子.  相似文献   

15.
从2,4-戊二酮和1,2,3-三溴丙烷出发合成了一类新的α-羰基二硫缩烯酮类化合物,并以其为底物合成了(4-甲基-1,3-二噻烷-2-亚甲基)-1,7-二芳基-1,6-二烯-3,5-二酮类化合物,通过IR和1H NMR方法对其进行了表征.  相似文献   

16.
The title compound N-(1-(2,4-dichlorophenyl)-1 H-pyrazolo[3,4-d]pyrimidin-4-yl)-4-(N,N-dipropylsulfamoyl)benzamide was synthesized by the condensation of 4-(dipropylsulfamoyl)benzoic acid with 1-(2,4-dichlorophenyl)-1 H-pyrazolo[3,4-d]pyrimidin-4-amine. This intermediate was prepared from 5-amino-1-(2,4-dichlorophenyl)-1 H-pyrazole-4-carbonitrile by the condensation with triethyl orthoformate and then cyclisation with ammonium hydroxide solution in tetrahydrofuran at room temperature. The crystal structure of the title compound was determined. The optimized geometric bond lengths and bond angles obtained by using density functional theory(DFT) have been compared with X-ray diffraction values. In addition, the preliminary biological test showed that the compound possesses distinct effective inhibition on the proliferation of some cancer cell lines.  相似文献   

17.
A series of pyrimidine methyl and polyfluoroalkyl ethers were synthesized from the reactions of trifluoroamine oxide (1) with several 5-substituted uracils in the presence of tetrabutylammonium hydroxide and methanol, 2,2,2-trifluoroethanol (6), or 1H,1H-pentafluoropropanol (7). With 5-(trifluoromethyl)uracil (2), the new ethers formed were 5-fluoro-5-(trifluoromethyl)-6-methoxypyrimidine-2,4-dione (8), 5-fluoro-5-(trifluoromethyl)-6-(trifluoroethoxy)pyrimidine-2,4-dione (9), and 5-fluoro-5-(trifluoromethyl)-6-(1H,1H- pentafluoropropoxy)pyrimidine-2,4-dione (10). With 5-chlorouracil (3), the new ethers 5-chloro-5-fluoro-6-methoxypyrimidine-2,4-dione (11), 5-chloro-5-fluoro-6-(trifluoroethoxy)pyrimidine-2,4-dione (12), and 5-chloro-5-fluoro-6-(1H,1H-pentafluoropropoxy)pyrimidine-2,4-dione (13) were obtained. With 5-fluorouracil (4), the new ethers 5,5-difluoro-6-methoxypyrimidine-2,4-dione (14), 5,5-difluoro-6-(trifluoroethoxy)pyrimidine-2,4-dione (15) and 5,5 difluoro-6-(1H,1H-pentafluoropropoxy)pyrimidine-2,4-dione (16) were found. By reaction of 5-nitrouracil (5), the new ethers 5-nitro-5-fluoro-6 methoxypyrimidine-2,4-dione (17), 5-nitro-5-fluoro-6-(trifluoroethoxy)pyrimidine-2,4-dione (18), and 5-nitro-5-fluoro-6-(1H,1H-pentafluoropropoxy)pyrimidine-2,4-dione (19) were obtained. Each of the new compounds was characterized by using IR, 19F and 1H NMR, and mass spectroscopy, and elemental analysis. A single-crystal X-ray diffraction study of 8 was helpful in confirming compound structure.  相似文献   

18.
Arylation of benzoxazolone 1 by 2,4-dinitrochlorobenzene 2 under solid-liquid phase transfer catalysis (PTC) gave 3-(2,4-dinitro)phenylbenzoxazolone 3 and 10-(2,4-dinitro)phenyl-3-nitrophenoxazine 4 . Neither PTC nor copper catalysis achieved arylation of 1 by less activated aryl halides.  相似文献   

19.
Reaction of 3,4,4-trichloro-1-(4-methylphenyl)-3-buten-1-one with amines results in replacement of the internal chlorine atom and is accompanied by prototropic allyl rearrangement leading to formation of the corresponding 3-amino-4,4-dichloro-1-(4-methylphenyl)-2-buten-1-ones. The reaction of the title compound with 2,4-dinitrophenylhydrazine yields 3,4,4-trichloro-1-(4-methylphenyl)-3-buten-1-one 2,4-dinitrophenylhydrazone and is not accompanied by allyl rearrangement.  相似文献   

20.
An alternate synthesis of 1-(2,4-dichlorophenyl)-4-(2-imidazolyl)-1-butanones 5d is presented after 1-[(dimethylamino)methyl- and 1-methyl]-2-lithioimidazole failed to be substituted satisfactorily by 2-(2,4-dichlorophenyl)-2-(3-iodopropyl)-1,3-dioxolane ( 3b ). The Pinner addition of ethanol to 2-(2,4-dichlorophenyl)-2-(3-cyanopropyl)-1,3-dioxolane yielded the corresponding imidate which was reacted with 1-amino-2,2-dimethoxyethane to form an amidine. Hot dilute hydrochloric acid converted this ami-dine to the 2-imidazolyl ketone 5b . Syntheses of homologous 1-(4-chloro- and 2,4-dichlorophenyl)-4-(2-imidazolyl)-1-pentanones 20 are described. Ketalizations of 5 and 20 with glycerol formed imidazolyl 1,3-dioxolanyl alcohols. Selective N- and O-alkylations of some of these imidazolyl alcohols are described.  相似文献   

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