1, 1'-二烷基-4, 4'-雙吡啶溴塩之質譜研究

A Mass Spectral Study on 1, 1'-dialkyl-4, 4'-bipyridinium Bromides

謝圳卿(Chun-Chin Hsieh) ； 王青柏(Ching-Bore Wang) ； 林隆清(Lung-Ching Lin)

《化學》 41卷2期 (1983/06) Pp. 47-54

https://doi.org/10.6623/chem.1983010

摘要

本篇為利用電子撞擊質譜學研究一系列之雙烷基－雙吡啶之鹵化塩類M^(++)（X^-）_2結構。實驗結果發現質譜儀不能測得此塩類之分子離子峯，但卻觀察到有更穩定之M^t峯，推測為由M^(2+)補捉－電子還原而成。當其溴塩之烷基碳數大於6時發現存在C_4H_8B_r^+的特性峯，另外由MX_2脫去二個HX而得之（M－.2）^+peak亦可測得，並發現當烷基的碳數不大時，皆存在m／z 156之基峯，及（M－R_1－R_2）^+。由以上之結果對雙烷基－雙吡啶溴塩之結構決定，可突破以前僅能以元素分析與核磁共振的方法，而以電子撞擊質譜分析。

並列摘要

The mass spectra of a series of 1, 1'-dialkyl-4, 4'-bipyridinium salts (viologens, M^(2+) (X^-)_2, X=Cl, Br, I) were studied by electron impact mass spectrometry. Although halide salts could not be detected as molecular ions in the mass spectrometer, an ion peak of M^+ was detected by the one electron reduction of the M^(2+) ion. When the carbon number of the alkyl group was longer than six, a characteristic peak of C_4H_8Br^+ was found from the bromide complexes. A peak corresponding to (M-2)^+ representing loss of HX from MX_2 was also found. Furthermore, when the carbon number of the alkyl group was not large, a base peak corresponding to (M-R_1-R_2)^+ was also obviously observed. By using the electron impact mass spectrometry, the structure of dialkyl-bipyridinium bromides could be determined.