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1.
从二炔丙基胺(1)出发,用二氯化钴和三苯膦经二(三苯膦)氯合然合成了戊二烯Ⅱ)配合物(8);用改进方法,八羰基二钴经多核然配合物10合成了双钴(Ⅱ)配合物11.分别考察了这两种不同价态的钴环配合物对富马酸二乙酯的反应活性,配合物8与活性烯烃2反应产生新的稳定的配合物9,配合物11则生成有机化合物3,根据配合物8的X射线晶体结构解释了Co(Ⅲ)对活性烯烃的反应活性。  相似文献   

2.
二烯丙基硫醚化合物的合成   总被引:2,自引:0,他引:2  
楚勇  赵敏政  徐鸣夏 《合成化学》2001,9(6):541-542
二烯丙基一硫醚(DS),二烯丙基二硫醚(DDS),二烯丙基三硫醚(DTS)和二烯丙基四硫醚(DTTS)等是大蒜提取液中的主要有效成分,具有十分广泛独特的生理药理活性。作者以甲酸、丙三醇为超始原料合成了这些化合物,烯丙基硫醚化合物总含量达83%,其中DDS,DTS含量分别达30%。产物均GC-MS鉴定确证。合成方法简单,原料易得,反应步骤少,实用性较强。  相似文献   

3.
用八羰基合二钴在相转移催化条件下合成1—萘乙酸   总被引:1,自引:0,他引:1  
戴金水 《应用化学》1998,15(1):86-87
1一荣乙酸是一种植物生长调节剂,也是合成茶乙酸甲酯(另一种优良的植物生长调节剂)的原料.其合成方法有多种“’“.本文研究了在常压下,利用CO。(CO)s在相转移催化条件下,使1一氯甲基素和一氧化碳直接反应,转化为帮乙酸的合成方法,气相色谱分析法研究了反应温度、催化剂用量等反应条件对转化率的影响.SP-3410型气相色谱仪(北京分析仪器厂),岛津IR-44O红外光谱仪(日本),EM-36060MHZ核磁共振仪(上海),HP5890-5971色谱一质谱联用仪(美国).l一氯甲基素(按文献[3」制备,纯度95%),八谈基合二钻(AR),…  相似文献   

4.
以硅酸钠为硅源、硫酸铝为铝源、CTAB为模板剂,采用水热法合成了负载型固体酸Al-MCM-41中孔分子筛催化剂,并通过X射线衍射(XRD)、热重差热分析(TG-DTA)、扫描电镜(SEM)和红外(IR)方法对其进行了表征,同时研究了该催化剂在二芳基乙烷合成反应中的催化性能。考察了各种反应因素的影响,确定其最佳合成条件为:原料苯乙烯与二甲苯质量之比为1∶7.5,催化剂用量为1 %(总投料质量百分比),反应时间为3 h,反应温度为140 ℃,产率可达87.1 %,比传统催化剂浓硫酸提高了17 %。研究结果表明,该催化剂是替代液体酸合成二芳基乙烷的理想固体酸催化剂。  相似文献   

5.
以5,6-二氢-6-烷基(芳基)-2H-吡喃-2,4-二酮(1)、芳胺(2)和原甲酸三乙酸进行缩合反应、合成了20个3-芳胺甲烯基-6-烷基(芳基)-5,6-二 喃-2,4-二酮(3),由于分子内氢键的合成,化合物3由一对构象异构体4和5组成,生物活性初步测定结果表明,这些化合物均有一定的杀菌活性。  相似文献   

6.
通过氯磺化反应,还原反应和低温相转移仙化反应合成了一种新型光学树脂单体合成 4,4′-二巯基二苯硫醚双甲基丙烯酸酯(MPSDMA),。成功地将苯环、含硫基团和双键引入光学树脂单体结构中,将MPSDMA分别与甲基丙烯酸甲酯(MMA)和苯乙烯(St)通过自由基共聚制成透明树脂,共聚树脂性能的研究表明该类新型光学树脂具有高折光指数,高表面硬度等特点。  相似文献   

7.
2,15-十六烷二酮的合成   总被引:1,自引:0,他引:1  
2,15-十六烷二酮的合成陈望忠焦子夏谢云德焦克芳(北京军事医学科学院毒物药物研究所100850)几十年来,人们研究和发展了许多合成麝香酮的方法[1],但是具有工业价值的方法报道甚少。主要难题是关键中间体难得、合成步骤过长、产率较低,其次是环合反应需...  相似文献   

8.
二溴对甲基偶氮甲磺(DBM-MSA)在磷酸介质中能与Ba(Ⅱ)、Sr(Ⅱ)形成稳定的络合物。研究了该显色体系的反应条件以及应用偏最小二乘法(PLS)处理两者叠吸收峰,建立了光度法同时测定Ba(Ⅱ)和Sr(Ⅱ)的方法。方法用于合成试样和除氧剂试样中两元素含量的测定,结果满意。  相似文献   

9.
以1,3-二乙烯基-1,1,3,3-四甲基二硅氧烷(DVS)为烯源与溴代芳烃通过Heck反应一步法合成了1,2-二苯乙烯(V-bisPh)及1,2-二苯并环丁烯基乙烯(V-bisBCB)。 优化了反应条件:DMF/H2O为溶剂,温度120 ℃,溴化物(R-Br)与烯源DVS的投料摩尔比为5∶1,反应48 h,1,2-二苯并环丁烯基乙烯产率为45.1%,1,2-二苯乙烯产率为48.6%。  相似文献   

10.
有机化合物PDBP的合成及其在催人反应中的应用   总被引:3,自引:2,他引:1  
用量子化学AM1方法优化了1-苯基二苯并膦(PDBP)和三苯基膦(TPP)的几何构型,比较了两种化合物的电子结构和空间结构,发现PDBP作为羧基合成铑膦催化剂的配体要优于三苯基膦(TPP);系统研究了PDBP的合成方法,其最佳合成条件为:在无水无氧的条件下,采用二乙胺锂与溴化四苯基膦摩尔比为3,反应温度为22℃,反应5h,反应后酸化,pH值为1-2,产物收率可达到85%-88%,采用元素分析、红外、核磁等方法,对其结果进行了表征,并将PDBP用于丙烯氢甲酰化反应的催化剂配体。实验证明,在相同的反应条件下,以其为配体的催化剂活性约是目前工业上使用的以三苯基膦为配体的催化剂的1.2倍,选择性约为其1.7倍。  相似文献   

11.
HTPB/TDI,HDI聚合反应动力学研究   总被引:4,自引:0,他引:4  
对端羟基聚丁二烯/甲苯二异氰酸酯,端羟基聚丁二烯/己二异氰酸酯甲苯溶液体系进行了反应动力学研究,用基团分析方法计算了相应体系的活化能,并对无催化剂和有催化剂的体系作了比较。结果表明,二丁基二月桂酸象对上述体系有强的催化作用,使体系的活化能降低,反应速度加快。对于对端差基聚丁二烯/甲苯二异氰酸酯体系,无催化剂时前后期反应活化能分别为29.1kJ/mol、37.4kJ/mol,有催化剂时前后期反应活化  相似文献   

12.
甲苯二异氰酸酯生成过程中间副产物结构的确定   总被引:1,自引:0,他引:1  
在重要有机化工原料甲苯二异氰酸酯的生产过程中经常会产生一些非目标中间体,严重地影响反应进程,确定这些中间副产物的结构对以应机理、改进反应条件具有极其重要的意义,采用核磁共振一振及二维HM-BC技术确定了该反应中的副产物结构,特地用其它分析方法难以确定的其苯环取代的位置进行了准确定位。  相似文献   

13.
Aqueous polyurethane dispersions were prepared by the reaction of hydroxyl-terminated poly(ethylene adipate), ethylene glycol, dimethylol propionic acid and aromaic diisocyante, 4,4′-diphenylmethane diisocyanate. The influence of molecular weight of oligoester and molar ratio between isocyanate and hydroxyl groups (NCO/OH) in the prepolymerization step were investigated. Molecular weight, particle size and particle size distribution were measured and compared. It was verified that the molecular weight increases with increasing in NCO/OH molar ratio. The results suggest that the hard segment content plays an important role in particle size and particle size distribution of the dispersions.  相似文献   

14.
四甲基苯二甲基二异氰酸酯基水性聚氨酯的合成和性能   总被引:1,自引:0,他引:1  
采用四甲基苯二甲基二异氰酸酯、聚酯二元醇和二羟甲基丙酸为原料,合成了一系列具有不同异氰酸根与羟基摩尔比(n(-NCO)/n(-OH))的聚氨酯乳液。 研究了n(-NCO)/n(-OH)对水性聚氨酯性能的影响。 结果表明,当该比值增加时,乳液的粒径增大,分布变宽,结晶性降低,耐热性下降,耐水性能呈现降低的趋势。 当异氰酸根与羟基摩尔比为3时,四甲基苯二甲基二异氰酸酯基水性聚氨酯的乳液粒径为10~30 nm,膜的分解温度达到275 ℃,24 h吸水率低于10%。  相似文献   

15.
Abstract

A gel permeation chromatographic method was developed for the quantitative analysis of toluene diisocyanate and diphenylmethane diisocyanate in polyurethane polymers. Standard curves were linear over the range of concentrations 2–35 μg/mL and a good correlation was established between the amount of diisocyanate injected and the peak height. In addition to rapid quantitation of diisocyanate monomers, the method developed also separates the polyurethane prepolymers and diisocyanate dimers and trimers, allowing analysis of components of commercial samples in a single step.  相似文献   

16.
Segmented polyurethanes (SPUs) which were expected to yield non-toxic degradation products were synthesized from lysine-based diisocyanate (LDI), 1,3-propanediol (PDO), and polycaprolactone diol (PCL). SPUs were synthesized via a standard two-step prepolymer method. The hard segment fraction was changed in order to tune the mechanical properties and the degradability. The aggregation structures of the SPUs were characterized by infrared spectroscopy and differential scanning calorimetry (DSC), temperature dependence of dynamic viscoelasticity, and small-angle X-ray scattering (SAXS). DSC and dynamic viscoelastic measurements revealed that the glass transition temperature (Tg) of the soft segment increased with an increase in the hard segment fraction. SAXS of SPUs revealed the aggregation states of hard and soft segments. Furthermore, the degradation of SPUs was investigated by exposing the polymers to a buffer solution at 310 K (pH=7.6). The degradation rate of SPUs increased with an increase in the soft segment fraction. This is because the soft segment has the hydrolyzable ester linkages and the ester linkages are susceptible to hydrolysis compared with the urethane linkages. Finally, an electrospray deposition method was used to fabricate biodegradable SPU micro-fibers. FE-SEM images showed that higher concentration of solution favored the formation of uniform biodegradable micro-fibers without beads-like structure.  相似文献   

17.
采用核磁共振波谱(NMR)研究了二苯基甲烷二异氰酸酯(MDI)在稀溶液中的水解反应机理.将同一MDI样品分别溶解在氘代氯仿、氘代丙酮和加入少量水分的氘代二甲基亚砜溶剂(DMSO)中,进行核磁共振氢谱(1H NMR)、核磁共振碳谱(13C NMR)测试.结果显示,MDI在含水的DMSO溶剂中测得的谱图与氘代氯仿、氘代丙酮中的差别显著.对该溶液进行了13C-1H异核近程相关(HMQC)、13C-1H异核远程相关(HMBC)及碳原子级数(DEPT 135)测试,并利用经验公式对其进行了详细归属,确认了反应产物的结构.分析得知MDI在含水溶剂中迅速反应,异氰酸酯基转化为脲基和氨基基团.异氰酸酯与水反应生成氨基基团,其与异氰酸酯反应活性比水高,对位取代氨基与水的竞聚率比值为7.1,邻位为1.4,对位取代氨基活性约是邻位的5倍.  相似文献   

18.
《Analytical letters》2012,45(11-12):2601-2611
Abstract

2, 4-toluene diisocyanate (TDI) in air was detected and determined by a piezoelectric quartz crystal sensor coated with tetrakis(hydroxyethyl)ethylenediamine (THEED)/dithizone(diphenylthiocarbazone) solution (l:3v/v in acetone). The response curve is linear over the concentration range 3–24 ppb of TDI. The sensor can be used for more than 2 months without loss in sensitivity and presented good reversibility and reproducibility. Of the different possible interferents tested, only SO2 caused a frequency change.  相似文献   

19.
Three diisocyanate units having different linearity and planarity on the basis of the arrangement of constituent aromatic rings are used to synthesize three polyurethanes (PUs) and the effects of the molecular structure of the diisocyanate units on phase separated morphologies of PUs have been studied. The linear and planar diisocyanate unit allows good packing of the hard segments in the hard domain by extensive intersegmental hydrogen bonding, and it forms a well ordered, long hard domain. However, the nonlinear and noncoplanar diisocyanate unit shows a lesser degree of hydrogen bonding in the short hard domain. Strong preferential orientation of the rigid/long hard domains inside a macroscopic grain boundary has been observed with the polarizing optical microscope especially for the PU based on the rigid diisocyanate. It was concluded that the molecular structure of the diisocyanate unit in PU plays an important role in determining the interchain interaction, the detailed phase‐separated domain structure, and local domain orientation in each grain boundary. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011  相似文献   

20.
New difunctional resin acids derivatives, diisocyanate, diurethanes and diureides were obtained via nitration of dehydroabietic acid followed by catalytic hydrogenation or reduction; carbonylation of the resulting amine and further reaction of the new diisocyanate with alcohols or amines.  相似文献   

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