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1.
有机磷杂环化合物的电子轰击正离子质谱已有报道。本文研究了18个具有植物生长调节活性的氮磷杂稠环有机磷化合物的电子轰击正离子质谱及其断裂机理。 实验采用VG-7070E双聚焦质谱仪和VG11-250数据处理系统,电子轰击源电子能量为70~100eV,离子源温度200℃,固体直接进样,温度100℃,RP=1000。采用B/E联动扫描研究亚稳断裂。试样的结构和纯度已用IR、~1H NMR、~(13)C NMR、~(31)P NMR、X-衍射及元素分析法测定。  相似文献   

2.
聚对二亚甲基苯的激光离解质谱分析高文德,刘维铬,王守文,马洪,敖十庆,邓万卉,许建光(四川联合大学成都610064)崔保顺,唐永建,马宏伟(中国工程物理研究院成都610003)关键词激光,质谱,聚对二亚甲基苯聚对二亚甲基苯难溶于有机溶剂且加热时立即分...  相似文献   

3.
新型芳基双西佛碱及其Ni(Ⅱ),Fe(Ⅲ)配合物的合成蓝仲薇,严洪兴,李莉,余孝其(四川大学化学系,成都610064)关键词西佛碱,合成,催化活性西佛碱除广泛用作螯合剂、稳定剂、分析试剂和生物活性剂以外。近年研究表明,其单核和双核金属配合物对于催化作...  相似文献   

4.
A new, convenient synthesis of alkyl and aryl 1-propenyl ether monomers in good to excellent yields has been developed. Alkyl and aryl allyl ethers can be smoothly isomerized to the desired 1-propenyl ethers by refluxing in a basic ethanolic solution containing pentacarbonyliron as a catalyst. A simplified two-step, one-pot procedure has also been developed which consists of combining an alcohol with allyl bromide in the presence of base and then adding pentacarbonyliron to isomerize the in-situ generated allyl ether to directly give the 1-propenyl ether. Good yields of alkyl 1-propenyl ethers were obtained using this process. Factors affecting the isomerization reaction were investigated and a mechanism was proposed.  相似文献   

5.
Three novel polymers incorporating Schiff bases,derived from condensation reactions of poly(acrylamide) with 5- chloro-2-hydroxybenzaldehyde,5-bromo-2-hydroxybenzaldehyde and 5-methyl-2-hydroxybenzaldehyde,have been synthesized,and their Cu(Ⅱ) and Ni(Ⅱ) complexes have been prepared.The ~1H-NMR signals of the—CH=N—and—NH_2 groups have been utilized to determine the relative abundances of Schiff base and acrylamide groups in the polymers containing Schiff bases.Poly(acrylamide) incorporating Schiff bases a...  相似文献   

6.
A mechanism of cleft-rate-determining-step of furfurol,furylacrylic acid,dimethylfuran,thiophene-2-aldehyde,and pyrrole-2-aldehyde is.proposed,and various quantum parameters of molecular ions of these compounds and their fragments are calculated by using CNDO/2 method.The peak-height of mass spectra is quantitatively interpreted.This method could be extended to heterocyclic conjugated compounds.  相似文献   

7.
蔥与菲的激发等离子体质谱的分析和比较   总被引:2,自引:0,他引:2  
蒽和菲是一对同分异构体,由于它们的结构都很稳定,所以在常规的电子轰击质谱中,它们的分子离子峰都很突出,两者的谱图没有明显的差异,不能成为一种鉴别手段.我们最近在自制的仪器上,记录了以近红外激光作用于这两个稠环芳香烃所产生的正负离子质谱,两者的谱图具有明显的不同,其中包含了较为丰富的结构信息,显示了这一研究手段的结构分析能力。  相似文献   

8.
Abstract

The electron impact mass spectra of 28 related phosphonates have been determined. Ethyl, iso-propyl and tert-butyl groups which are bound directly to phosphorus, fragment to the corresponding alkenes; similar iso-propyl and tert-butyl groups in the dimethyl esters also fragment to ethylene and propene respectively, i.e. the P-alkyl group rearranges with transfer of the elements of a methyl group to the phosphorus ion. The diethyl alkenephosphonates undergo double hydrogen rearrangements of an ethoxy group to give dihydroxyphosphonium ions. The di- and trihydroxyphosphonium ions have a characteristic fragmentation which involves loss of water. This characteristic has been used as evidence for the rearrangement of a phosphacylium ion to a dihydroxyphosphonium ion. Some other unusual rearrangements involving the combination of the groups bound to phosphorus and oxygen have been observed.  相似文献   

9.
本文应用低分辨负离子电子轰击质谱及亚稳分析数据,研究了10种硫代磷酯酸化合物的负离子质谱特征,探讨了其碎裂规律。指出取代基的性质及其位置对分子异构化重排有明显影响。  相似文献   

10.
研究了二甲氨基苄叉亚胺类化合物溶液的电子光谱。结果表明一端为电子给体另一端为电子受体的共轭型取代苄叉对硝基苯胺3,在基态下发生了分子内电荷转移,其跃迁吸收波长比化合物1,2(315 nm)红移90 nm。以乙撑基联接的非共轭型苄叉亚胺奥化合物4,5,6未观察到基态时的电荷转移现象,但在激发条件下可明显的发生分子内的电荷转移而使荧光强度大大减弱。MMA等对1的荧光有明显的猝灭作用,表明其间发生了电荷转移。丙烯酸则因会引起西佛碱的水解,而使荧光减弱。  相似文献   

11.
12.
本文所研究的7种N-取代苯并咪唑和硫代噻唑烷酮类化合物是一类新合成的具有较高杀菌活性的化合物。本文利用电子轰击质谱技术对表中所列的化合物进行了研究。在高分辨精确质量测量和亚稳离子测定的基础上着重讨论了分子内3、4位C—C键的断裂和与杂环  相似文献   

13.
Abstract

The first, detailed analysis of the mass spectra of the title compounds having a pyranoid or furanoid ring was carried out. The molecular-ion intensities of these phosphorus sugars were shown to be higher compared to the oxygen analogues, thus permitting accurate mass measurement. The main fragmentation pathway was the consecutive loss of the substituents from ring carbon atoms and C-6 (the A series of fragmentation), leading to the formation of 1,2-dihydro-λ5-phosphorin or -phosphole oxide derivatives. Possible degradation pathways of the phosphorus-containing ring to acyclic fragments are also discussed. These findings are considered to be of use in structural analysis of these phosphorus sugars.  相似文献   

14.
Fluorescence spectra of ladderlike polyphenylsilsesquioxane (LPPS) and ladderlike 1,4-phenylene-bridgedpolyvinylsiloxane (LPPVS) have been measured as a function of temperature (4-55℃), in dilute tetrahydrofuran solution.The excimer (I_E) to monomer (I_M) intensity ratio (I_E/I_M) of LPPS dilute solution shows a double linear Arrhenius plot with abreak point ascribable to a transition temperature T_t This behavior has not been found for single chain polyorganosiloxanes.When InI_E of LPPS was plotted against I/T it also gave a double linear plot with one break point, which was found in singlechain polyorganosiloxanes. The different behaviors between LPPS and single chain polyorganosiloxanes may be mainlyattributed to the relatively rigid double-chain macromolecular backbone of LPPS. However, the In(I_E/I_M) of dilute LPPVSsolution versus I/T shows a simple linear variation with a positive slope which confirms our proposition. The differencebetween the fluorescence results of LPPS and those of LPPVS may possibly derive from their structure differences andcooperative motion in backbone chain bonds.  相似文献   

15.
Abstract

The oxovanadium(IV) complex of the ligand, N,N'-bis-(salicylidene)-1,1-(dimethyl)ethylenediamine, has been prepared. It has a magnetic moment of 1.76 B.M., which is almost invariant over a range of temperature. The electron paramagnetic resonance spectrum of the powder has been measured at 296° and 80°K, while that of the solution was measured at 296°K (go ≈ 1.97 and A0 ≈ 90 × 10?4 cm?1). The magnetic moment of the complex agrees with that calculated from the paramagnetic resonance g values taken at 80°K. Furthermore, the complex has been characterized by mass spectra, infra-red, ultra-violet and visible spectra, conductivity, osmometry and polarimetry.

All evidence suggests that the complex is a tetragonal-pyramid.  相似文献   

16.
铈离子与氨基甲酸酯类化合物引发丙烯酰胺聚合的研究   总被引:2,自引:1,他引:2  
本文对铈离子与苯基氨基甲酸酯类化合物在H_2O-CH_3CN(3∶1,V/V)及H_2O-HCONH_2(1∶2,V/V)两种介质中引发丙烯酰胺的聚合进行了研究。考察了不同结构的苯基氨基甲酸酯对聚合的影响。苯基氨基甲酸酯类化合物对铈离子引发聚合均有促进作用,其中对-甲苯基氨基甲酸酯的促进作用最为显著。测定了聚合反应表现活化能及聚合动力学方程,并提出了聚合反应机理。  相似文献   

17.
Abstract

The mass spectra of some 2-thiophenemercuric derivatives are determined and the fragmentation interpretations are based on mechanistic analogy and supported in some cases by metastable peaks and low energy mass spectra. They all fragment ultimately to the 2-thienyl cation formed either through a two-step process, by cleavage of Hg[sbnd]X bond to give the 2-thienylmercuric cation, followed by extrusion of mercury, or by a one-step process through cleavage of carbon-mercury bond. Their base peaks being the C3H3 +ion (m/e 39).  相似文献   

18.
芳香族二胺聚合物的合成及其性能   总被引:1,自引:0,他引:1  
<正> 在导电性有机固体研究领域中导电聚合物的研究占有不可忽视的地位,特别是70年代以来聚苯胺及其掺杂物导电性的发现更加引起了人们对有机导体的极大兴趣,人们从聚合物的合成到性能的表征展开了广泛研究,主要工作集中在聚苯胺、聚吡咯等各种合成方法及电性能表征方面。有关芳香族多胺聚合物的合成及表征却很少见文献报道,Tsuchida等人曾报道了在铁盐与含氮化合物形成的络合物存在下对苯二胺及对苯二酚氧化聚合得到具有顺磁性、电导率为10~(-10)Scm~(-1)的聚合物。80年代末期Torrance报道了在较缓和的条件下均苯三胺聚合可以得到铁磁性聚合物,本文对三种苯二胺聚合物的合成及其电性能、热稳定性能等做了初步研究。  相似文献   

19.
分子内电荷转移化合物的光谱和光物理   总被引:2,自引:0,他引:2  
近年来,分子内电荷转移化合物光物理行为的研究受到了广泛的注意,这是由于这类化合物分子的发光性能强烈地受其周围溶剂性质的影响.它们常被考虑作为研究溶剂-溶质间相互作用以及溶剂分子弛豫的有效探针化合物.Loutfy等曾对被束缚的及未被束缚的N,N-二甲基氨基苄叉二腈类化合物的光物理行为作过详细研究.指出它们的荧光量子产率和该类化合物分子的刚性以及和母体环境的粘度、温度及物理化学性质等密切有关,它们  相似文献   

20.
标题化合物K8H(BW11O39)·13H2O属立方晶系,空间群P43m,a=10.710(1)Å,V=1228.58Å3,Z=1;DO=4.39g·cm-3,Dc=4.42g·cm-3。(BW11O399-离子属于不饱和α-Keggin型结构,B原子位于O2四面体的中心。测定并研究了化合物的IR和Raman光谱性质。  相似文献   

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