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报道了8个2,4-二氨基-5-取代苄基嘧啶衍生物的电子轰击质谱及碰撞活化解离和质量分析离子动能谱.该谱提供了化合物醚键及2,4-二氨基-5-取代苄基嘧啶环的主要碎裂途径,总结了一些裂解规律,将有助于这类化合物的结构推断。 相似文献
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气相二茂铁双电荷离子的动能谱研究 总被引:1,自引:0,他引:1
The unimolecular charge separation reactions of the doubly charged ions FeC_(10)H_(10)~(2+)、FeC_(10)H_9~(2+)、FeC_(10)H_8~(2+) produced in the ion source by electron impact from ferrocene have been studied using Mass analyzed Ion Kinetic Energy Spectrometry (MIKES) technique. From the values of the kinetic energy releases (T), the intercharge distances (R) of the exploding doubly charged ions in their transition structures have been estimated and some structural informations about the transition states can be obtained. The collision induced reactions of the FeC_(10)H_(10)~(2+) ion with Ar have been studied using MIKES, we postulate a new type of continuing reaction which may be "collisional charge separation induced dissociation". 相似文献
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The unimolecular dissociation reactions of doubly charged ions were reported,which resulted from a tandem mass spectrometer and a reversed geometry double focusing mass spectrometer by electron impact.Mass analyzed ion kinetic energy spectrometry(MIKES) was used to obtain the kinetic energy releases in charge separation reactions of doubly charged ions.The intercharge distances between the two charges at transition states can be calculated from the kinetic energy releases.Transition structures of unimolecular dissociation reactions were infered from MIKES and MS/MS. 相似文献
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具有生物活性有机锗化合物的质谱特征 总被引:1,自引:0,他引:1
电子轰击源、质量分析离子动能谱、峰匹配测定精确质量等方法和技术,对9种新的具有一定生物活性的有机锗化合物进行了较深入的质谱研究,分析了它们的质谱碎裂途径,总结了质谱特征。 相似文献
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在EI源条件下,作出了5个三「(二甲基乙基硅基)亚甲基」锡双硫代磷酸酯的常规质谱,利用高分辨确定了该系列化合物中相对于丰度最大离子的元素组成,并推出可能的离子结构,借助于MIKES谱,找出了主要离子的子离子,以此研究了该系列化合物主要离子的形成途径和质谱规律。 相似文献
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Electron impact-induced fragmentation mechanism of Trans-α-Aryl-β-enamino esters were investigated using mass-analyzed ion kinetic energy (MIKE) spectrometry and high resolution accurate mass data It was found that the main characteristic fragmentations of compounds studied were:an odd electron ion M^ -EtOH was formed by losing a neutral molecule of ethanol;and the skeletal rearrangements took place;and the ring opening reaction happened after losing a carbon monoxide;and the typical McLafferty rearrangement underwent in ester group.The cycliztion reation caused by losing neutral molecule of TsNH2 due to the ortho-effects of substituted group of gromatic ring was also observed. 相似文献
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双电荷离子[C_(12)H_(12)N_2O]~(2+)和[C_(12)H_(12)N_2S]~(2+)的气相单分子分解反应研究任达,贾维平,李智立,刘淑莹(中国科学院长春应用化学研究所,长春,130022)关键词双电荷离子,质量分析离子动能谱,串联质谱,4... 相似文献
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Introduction Substituted benzaldoxime 3-( 2, 2-dichlorovinyl )-2,2-dimethyl cyclopropanecarboxylates,considered as pyrethroid analogs, show a good bioactivity such as fungicidal, herbicidal and plantgrowth regulating activities[1,2]. EI-MS spectra of those compounds show the rearrangement of their structures, which has prompted us to elucidate their behavior under EI conditions. All the compounds studied have M-165 and M-99 fragment ions in the EI-MS spectra, but there is no segment with the mass of 165 and 99 lost directly from the molecular ions. So we postulated the process of rearrangement, it involved the cleavage of the C2C3 bond in the substituted cyclopropyl accompanied by the migration of disubstitued methylene-amino moiety to C2 or C3 position and elimination of a conjugated group with the mass of 165 or 99 to afford the even electron ion, of which the important step is the cleavage of the N-O bond. Although the cleavage of the alkoxy bond in the pyrethroids[3-5] has been reported, there has been no rearrangement reported. In order to test our postulations, MIKES and EI-HR-MS were carried out to elucidate the fragmentation pathways. The substituents in the phenyl ring played important roles in the stabilization of the product ions. The focal point of our work was to investigate two pathways of the skeletal rearrangement and the effect of the substituents. 相似文献