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1.
本文合成了四个VO(PMBP)_2·nL型加合物,元素分析确定其组成为VO(PMBP)_2·2H_2O、VO(PMBP)_2·py、VO(PMBP)_2·β-MP·H_2O、VO(PMBP)_2·γ-MP,其中PMBP、py、β-MP、γ-MP分别为1-苯基-3-甲基-4-苯甲酰吡唑酮-5,吡啶,3-甲基吡啶、4-甲基吡啶.通过摩尔电导、差热热重分析、红外光谱、电子光谱、顺磁共振波谱等方法研究了加合物的性质.  相似文献   

2.
合成了一系列VO(β-dik)_2L类型加合物,其中β-dik分别为苯甲酰丙酮,2-噻吩甲酰三氟丙酮,L3-甲基吡啶、4-甲基吡啶、吗啉、异喹啉,VO(bza)_2Mor、VO(tta)_2Mor、VO(tta)_2iso-q为首次合成,并通过元素分析、摩尔电导、红外光谱、电子光谱、顺磁共振波谱等对加合物进行了较系统的表征工作。  相似文献   

3.
尾式卟啉铁配合物与有机碱的加合作用   总被引:1,自引:0,他引:1  
曹锡章  修正坤  牟西海  赵东源 《化学学报》1985,43(11):1043-1047
本文用分光光度法研究了一种新的尾式卟啉铁氯化meso-[邻-(4-二乙氨基丁酰氨基)苯基]三苯基卟啉合铁(III)[PFe(III)Cl与咪唑、苯骈咪唑、吡啶、3,5-二甲基吡啶、三乙胺、二乙胺、正丁胺的加合作用,测定了这些有机碱同卟啉铁的加合平衡常数,实验结果表明:咪唑类与卟啉铁作用一步生成2:1的加合物;吡啶类与卟啉铁作用分步生成1:1和2:1的加合物;胺类与卟啉铁作用只生成1:1的加合物,同时还发现胺类的平衡常数K与BH[+]的酸常数K之间的关系式为logK=6.45Pk-66.87。  相似文献   

4.
本文合成了四个VO(PMBP)2·nL型加合物,元素分析确定其组成为VO(PMBP)2·2H2O、VO(PMBP)2·py、VO(PMBP)2·β-MP·H2O、VO(PMBP)2·γ-MP,其中PMBP、py、β-MP、γ-MP分别为1-苯基-3-甲基-4-苯甲酰吡唑酮-5,吡啶,3-甲基吡啶、4-甲基吡啶.通过摩尔电导、差热热重分析、红外光谱、电子光谱、顺磁共振波谱等方法研究了加合物的性质.  相似文献   

5.
张红  刘文杰  曹德榕  江焕峰 《化学学报》2011,69(17):2070-2074
2-溴-4-甲基吡啶(1)经氯代和碘代反应合成了2-溴-4-碘甲基吡啶(3),3和蒽酮(4)反应生成10,10-二(2-溴-4-吡啶甲基)-9(10H)蒽酮(5),5在3 MPa下与NaOCH3反应得到10,10-二(2-甲氧基-4-吡啶甲基)-9(10H)蒽酮(6),6经硼氢化钠还原得到蒽醇(7),7在对甲苯磺酸催化...  相似文献   

6.
2-,3-和4-溴甲基吡啶的水解反应的动力学研究   总被引:1,自引:0,他引:1  
用HPLC测定了2-、3-和4-溴甲基吡啶在60℃、离子强度μ为0.15、pH 0.9~9.9的缓冲溶液中水解成相应的羟甲基吡啶的反应速度.通过数学处理,求得溴甲基吡啶的一级和二级反应速度常数以及溴甲基吡啶共轭酸的一级反应速度常数.水解反应的可能机理是SN1和SN2.  相似文献   

7.
对手性唑硼烷催化3,3-二甲基丁酮-2不对称还原反应机理进行了从头算研究.结果表明,该不对称还原反应是放热的.反应经历了催化剂-硼烷加合物、催化剂-硼烷-酮加合物、含B-O-B-N四元环的催化剂-烷氧基硼烷加合物的生成,以及催化剂-烷氧基硼烷加合物的离解并再生催化剂等过程.在催化剂-硼烷-酮加合物经氢转移而生成催化剂-烷氧基硼烷加合物的过程中,氢转移与B-O-B-N四元环的形成是协同进行的.氢转移是还原反应的控制步骤.氢转移过渡态具有扭曲的椅式结构,所决定的还原产物是与实验相吻合的R手性醇.  相似文献   

8.
对手性噁唑硼烷催化3,3-二甲基丁酮-2不对称还原反应机理进行了从头算研究.结果表明,该不对称还原反应是放热的.反应经历了催化剂-硼烷加合物、催化剂-硼烷-酮加合物、含B-O-B-N四元环的催化剂-烷氧基硼烷加合物的生成,以及催化剂-烷氧基硼烷加合物的离解并再生催化剂等过程.在催化剂-硼烷-酮加合物经氢转移而生成催化剂-烷氧基硼烷加合物的过程中,氢转移与B-O-B-N四元环的形成是协同进行的.氢转移是还原反应的控制步骤.氢转移过渡态具有扭曲的椅式结构,所决定的还原产物是与实验相吻合的R手性醇.  相似文献   

9.
2-甲基吡啶的电氧化研究   总被引:2,自引:2,他引:2  
在质子交换膜的电解槽内,以PbO2/Ti为阳极,通过稳态极化曲线测量,考察了温度、硫酸浓度和2-甲基吡啶浓度对2-甲基吡啶电氧化的影响.通过正交试验和高效液相色谱分析确定了电氧化2-甲基吡啶的最佳条件.  相似文献   

10.
发展了一个无光敏剂参与的可见光促进的咪唑并[1,2-a]吡啶衍生物的三氟甲基化新反应.该反应利用本课题组此前发展的基于硫叶立德骨架的亲电三氟甲基化试剂作为三氟甲基自由基源,反应条件温和,底物普适性好,同时兼容常见的官能团.机理研究表明该反应可被自由基捕获剂阻断.对两个反应底物及它们的1∶1混合物的紫外-可见光吸收光谱进行了研究,研究表明三氟甲基化试剂与咪唑并[1,2-a]吡啶之间形成了一个Donor-Acceptor加合物.在此基础上提出了一个合理的机理,即该加合物在光照条件下被激发,发生硫-三氟甲基键均裂生成三氟甲基自由基,该自由基与咪唑并[1,2-a]吡啶发生自由基取代反应.同时也成功地将该方法应用于治疗胃溃疡药物佐利米定的三氟甲基化衍生物的合成.  相似文献   

11.
The extraction behavior of Th(IV) from dilute nitric as well as perchloric acid medium using 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) and its mixture with tri-n-octyl phosphine oxide (TOPO) was investigated. The species of the type Th(X)(PMBP)3·(HPMBP) and Th(X)(PMBP)3·(TOPO) were extracted for the binary and ternary extraction systems, respectively, where X=NO3− or ClO4−. The presence of 1.25·10−5M Th carrier in the aqueous phase resulted in the extracted species of the type of Th(PMBP)4 and Th(PMBP)4·(TOPO), respectively. The extraction constant (logk ex ) for the binary species Th(PMBP)4 was found to be 6.89±0.01 while the overall extraction constant (logK) for the ternary species Th(PMBP)4·(TOPO) was calculated to be 13.17±0.06.  相似文献   

12.
Conditions for neptunium recovery from nitrate solution containing large amounts of uranium by extraction with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (PMBP), and a mixture of PMBP with di-2-ethyl-hexylphosphoric acid (HDEHP) were studied. A two-stage technique, based on removal of uranium macroamounts at the first stage by means of extraction of uranium with PMBP and HDEHP mixture, and neptunium extraction by PMBP at the second stage, was suggested.  相似文献   

13.
Coronel FT  Mareva S  Yordanov N 《Talanta》1982,29(2):119-123
The extraction of uranium(IV) from phosphoric acid solutions with PMBP and PMBP-TOPO mixtures has been studied. The synergic extraction with PMBP-TOPO is more effective than the simple chelate extraction with PMBP and both systems are more effective than the synergic extraction of uranium(VI) with DEHPA-TOPO. It is established that the complexes extracted are U(PMBP)(4) and U(PMBP)(4).TOPO for the chelate and synergic extraction respectively. The most probable uranium(VI) species in the aqueous phase (2.9-6.33M H(3)PO(4)) is the neutral complex U(H(5)P(2)O(8))(4). Analytical methods suitable for determination of uranium in phosphoric acid solutions have been developed. The highest sensitivity is achieved by combining the synergic extraction with the uranium(IV)-arsenazo III colour reaction.  相似文献   

14.
The scandium complexes of Sc(PMBP)3·H2O (non-crystal) and Sc(PMBP)3 (crystal) with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) were prepared and characterized by thermal analysis, IR, NMR and MS spectroscopies. The crystal structure of the complex, obtained by X-ray analysis, indicates that PMBP is a bidentate ligand in the complex and that the Sc atom is six-coordinate and is in a meridional octahedral environment. The order of the ring current effect on the pyrazolone ring is Sc(PMBP)3 >PMBP(enol)> PMBP(keto).

The metal to ligand stoichiometry was found to be 1:3. The crystalline complex melts at 209 °C, followed by degradation at about 310 °C, with the beginning of decomposition. The enthalpy of melting was found to be 61 kJ/mol. On the other hand, the non-crystalline complex was found to change into a crystalline complex at 176 °C with an exothermic reaction before melting at 217 °C. The IR band observed at approximately, 450 cm−1 is possibly due to the stretching of the Sc–O bond.  相似文献   


15.
Gao J  Hu G  Kang J  Fan H  Bai G 《Talanta》1994,41(4):541-546
In this paper, liquid-liquid extraction behaviour of RE(III) (RE = La, Sm, E, Yb) by the use of 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (PMBP) in liquid paraffin with cersin has been investigated at 343.2 K. Under some conditions, the synergistic extraction behaviour with PMBP and Phen has also been studied. The slope analysis method shows that the compositions of the extracted species are REA(3) and REA(3)B. pH(1 2 ) values were also obtained. Equilibrium extraction constants and thermodynamic parameters were calculated. The results showed that increasing temperature is favourable to extraction of heavy rare earth ions with PMBP and more favourable to synergistic extraction with PMBP and Phen. Synergistic extraction can be carried out at lower pH.  相似文献   

16.
The synergistic extraction of Zn(II) has been studied in the PMBP—TBP system (where PMBP = 1-phenyl-3-methyl-4-benzoyl-pyrazole-5-one and TBP = tri-n- butyl phosphate) at various temperatures using a radiochemical technique. The thermodynamic parameters for the reactions involved support the mechanism for the synergistic extraction in which the 5-coordinate monohydrated Zn(PMBP) 2 chelate exchanges a water molecule for TBP.  相似文献   

17.
AuCl_3·HCl·4H_2O和TiCl_4分别与1-苯基-3-甲基-4-苯甲酰基吡唑酮-5(酮式HPMBP)的饱和乙醇溶液反应,首次合成了化学式为Au(HPMBP)(PMBP)_3和Ti(PMBP)_2(OEt)Cl(OEt=OC_2H_5~-)的螯合物。用元素分析、IR、~1HNMR、电导和质谱(MS)研究了它们的性质,推测出了分子结构式。  相似文献   

18.
The use of 1-phenyl-3-methyl-4-benzoylpyrazolone (PMBP) as extractant for separation of Fe(III) and Fe(II) and low-temperature vaporization of the Fe(III)–PMBP chelate into ICP-AES for their speciation analysis was investigated. The factors affecting the formation of Fe(PMBP)3 chelate and its vaporization behavior were investigated in detail. PMBP was used not only as the extractant for the separation of Fe(III) and Fe(II) but also as the chemical modifier for the low-temperature ETV-ICP-AES determination of iron. Under the optimized conditions, the detection limit for iron(III) and iron(II) are both 3.2?ng/mL, with relative standard deviations of 3.9 and 4.5%, respectively. The proposed method was applied to the determination of trace iron in biological standard reference materials and the species in East Lake water samples, and the results obtained were satisfactory.  相似文献   

19.
A study on extraction of thorium with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (PMBP)-loaded polyurethane foam is described. Open-cell polyurethane foam has proved to be effective as supporting material for PMBP. Thorium nitrate can be quantitatively extracted by PMBP-loaded polyurethane foam over a wide pH range. The effect of equilibrium time, pH, thorium concentration, various anions and flow-rate on the extraction efficiency of thorium is examined. A technique of extraction chromatography column with PMBP foam cylinder has been developed for trace thorium analysis of bulky water samples.  相似文献   

20.
Liquid liquid extraction of 46Sc was studied with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP). It has been found that PMBP extracts almost quantitatively scandium from 10-3 to 10-2M HCl solutions. Tributyl phosphate (TBP) has a pronounced antagonistic effect on the extraction process.  相似文献   

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