质谱学报2017，Vol.38Issue(6)：620-629,10.DOI:10.7538/zpxb.2016.0184
MSTFA及其含氟衍生物的特征质谱重排反应
Analysis of MSTFA and Its Fluorine Derivatives Using Mass Spectrometry
王毅 1张苹 1吴生秀 1何敏 1孙媛媛 1赵彤1
作者信息
- 1. 西安瑞联新材料股份有限公司,陕西西安 710077
- 折叠
摘要
Abstract
Chemical conversion of a compound to an appropriate derivative can some-times improve the resulting mass spectral data ,either by increasing the compound's vapor pressure or by making its spectrum more easily interpretable .As a kind of impor-tant derivative reagent ,the attribution of mass spectrum peak in trifluoro-N-methyl-N-(trimethylsilyl) acetamide (MSTFA) has a great significance to further investigating its reaction mechanism .Through studying the fluorinated and non fluorinated derivatives as well as fluorinated aromatic phenolic compounds by gas chromatography mass spec-trometry (GC/MS) ,it was found that fluorinated derivatives have characteristic m/z 77 even electron fragment ions ,and non fluorinated derivatives can not form this character-istic ions . High resolution mass spectrometer confirms above characteristic ions is C2 H6 FSi+ ,indicating skeleton rearrangement has an important effect on the formation of m/z 77 fragment ions .Therefore ,the formation way may be unimolecular nucleophil-ic reactions (SN 1):oxygen (nitrogen) is intermediate in its ability to influence either αor i reactions .In an aliphatic ether attraction of an electron pair initiated by the localized positive charge on the oxygen (nitrogen) can form the trimethylsilane ion and the alkox-yl radical .First molecular ion by α-cleavage loss of methyl radical at a reactive site ,pos-itive charge localized on the oxygen (nitrogen) atom .Because the positive charge attract a couple of electrons migrate ,the charge site is moved localized on the silicon atom , then fluorine atom carries a couple of electrons nucleophilic attack on the silylium ion , and O(N)—Si bond's a couple of electrons migrate ,and nucleophilic elimination reac-tion in intramolecular is occur .The mechanism of these fragmentations has been studied with the GC/MS analysis and deuterium labeled analogs whose preparation is reported .关键词
N-甲基-N-(三甲基硅烷)三氟乙酰胺(MSTFA)/气相色谱-质谱法(GC/MS)/三甲基硅烷衍生物/含氟衍生物/骨架重排Key words
trifluoro-N-methyl-N-(trimethylsilyl) acetamide (MSTFA)/gas chroma-tography mass spectrometry (GC/MS)/trimethylsiyation derivatives/fluoro deriva-tives/skeletal rearrangement分类
化学化工引用本文复制引用
王毅,张苹,吴生秀,何敏,孙媛媛,赵彤..MSTFA及其含氟衍生物的特征质谱重排反应[J].质谱学报,2017,38(6):620-629,10.
