【作者】 崔晓楠；

【导师】 莫卫民； 曹小吉；

【作者基本信息】 浙江工业大学 ， 应用化学， 2011， 硕士

【摘要】 随着质谱技术的不断的发展及其在各个领域的应用不断深入,质谱技术备受关注。本论文应用大气压离子源串联质谱技术对二茂铁衍生物、镍的菲咯啉配合物以及新型配体双烯取代苯衍生物的断裂机理进行了研究和探讨,分析了这些化合物分子的断裂活性位点。同时还用电子轰击电离源研究了新型配体双烯取代苯衍生物的质谱断裂机理,并与大气压离子源串联质谱下的裂解机理进行了比较。首先,采用电喷雾电离多级串联质谱技术,研究了二茂铁衍生物取代基类型及位置对二茂铁衍生物的质谱裂解途径的影响,结果发现,取代基的电子效应及空间位阻效应是决定该类化合物的质谱断裂位点至关重要的因素。二茂铁胺甲酰类衍生物带有吸电子基团时,胺甲酰基上的N原子比O原子的质子化能力强,易产生C-N键断裂的碎片离子;而二茂铁亚甲胺类衍生物的质子化位点则在二茂铁的母核上,因而此类衍生物易产生环戊二烯分子的中性丢失;二茂铁甲酰类衍生物产生的碎片离子是由甲酰基两端断裂产生的。其次,采用电喷雾电离多级串联质谱技术,研究了镍的菲咯啉配合物在质谱中的裂解规律,实验结果表明,镍的菲咯啉配合物的特征断裂是配体的中性丢失;另一方面,对于分子结构中含有活泼氢的配合物,在质谱断裂过程中还会发生配体间的质子转移反应,从而生成质量互补的一价离子对。有意思的是,在碰撞裂解过程中,镍的菲咯啉配合物还会产生明显的溶剂化效应,同时此现象还与配合物的价态和配位数有关:当配合物的价态为二价且配位数为4或配合物的价态为一价且配位数为2时,配合物及其碎片离子易与溶剂分子（CH₃CN、CH₃OH和H₂O）发生配位。最后,采用电子轰击离子源和大气压化学电离源技术,对新型配体双烯取代苯衍生物的质谱裂解规律进行了研究,比较了取代基类型及位置的不同对化合物质谱裂解途径的影响。结果发现,这些化合物都有丢失Br和Cl自由基的现象,且在质谱断裂中该类化合物都会发生骨架重排反应,形成稳定的五元环结构。更多还原

【Abstract】 The mass spectrometry has been concerned extensively with the rapid development of new mass spectrometry technologies and has developed in many fields greatly. In this thesis, the fragmentation mechanisms and the active cleavage sites of ferrocene compounds, nickel phenanthroline complexes and diene ligands were studied using tandem mass spectrometry with atmospheric pressure ion source. On the other hand, the fragmentation pathways of diene ligands were also investigated by electron impact （EI） ion source. Furthermore, the fragmentation mechanisms of diene ligands by these two kinds of ion sources were compared in detail.First, the fragmentation mechanisms of ferrocene compounds were discussed using collision induced dissociation （CID） with electrospray ionization （ESI）. As the results shown, the cleavage sites were closely related to electronegativity and steric effect of substituents. For formamide ferrocenes with electron-withdrawing group, the protonated-ability of N atom is stronger than that of O atom, which will promote the breakage of C-N bond of formamide group. However, in the CID process, the neutral loss of cyclopentadienyl is dominated for methylenimine ferrocenes due to the protoned site on the ferrocene nucleus. Different from the former compounds, the fragment ions of formoxyl ferrocene were formed by the cleverage of formoxyl.Secondly, fragmentation mechanisms of the nickel phenanthroline complexes were also investigated by ESI. The leading fragment ions were produced by neutral loss of ligand from complexes ions. Furthermore, for the complexes containing ligand with active H, the interligand proton transfer reaction occurred. As a result, the complemental monocation pair generated. Amazingly, these complexes were liable to be solvated by various solvents （CH₃CN, CH₃OH and H₂O）, which had great relationship with the valence and coordination number of the complexes. When the complexes were divalent with two ligands or univalent with one ligand, the complexes were apt to coordinate with the solvent moleculars （such as CH₃CN, CH3OH and H₂O）.Finally, for the diene ligands, the effect of substituents on the fragmentation mechanisms was evaluated using EI source and APCI source, respectively. It was easily to lose Br and Cl radical. Moreover, the skeletal rearrangement reaction, which a five-membered ring formed, was favored in the fragmental process.更多还原