The synthesis of the seven isomeric methylchlorooctanoates is reported, in most cases for the first time, and their spectral characteristics are described and studied. Hypotheses are advanced to explain the abnormal spectral behaviour of some of them. The mass spectra show scrambling of hydrogen/chlorine and/or the chain carbons, as well as low ability to undergo the McLafferty rearrangement, in some
在大多数情况下,这是首次报道了七个异构体氯辛酸甲酯的合成,并对其光谱特性进行了描述和研究。假设被用来解释其中一些的异常光谱行为。在某些情况下,质谱显示氢/氯和/或链碳的加扰,以及进行麦克拉菲重排的能力低。给出了一套完整的13 C NMR参数,包括所有位置的取代基效应,发现除三个值外,系列中的各个位置都具有出色的相干性。
Korhonen, Ilpo O.O.; Korvola, Jorma N. J., Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry, 1981, vol. 35, # 6, p. 461 - 464
作者:Korhonen, Ilpo O.O.、Korvola, Jorma N. J.
DOI:——
日期:——
Mass spectra of halogenated esters. 7. Methyl esters of 2-chloro C2C20n-alkanoic acids
作者:Ilpo O. O. Korhonen
DOI:10.1002/oms.1210231010
日期:1988.10
AbstractThe mass spectral fragmentation of a homologous series of methyl esters of 2‐chloro n‐alkanoic acids ranging from acetic (C2) to eicosanoic (C20) acid on electron impact has been investigated. The fragmentation pathways were elucidated with the aid of the first field‐free region metastable ions, the results being presented with one compound, i.e. with ionized methyl 2‐chloro‐octauoate. Owing to the Cl/H exchanges and to the formation of the non‐chlorinated parent esters prior to the fragmentations the spectra show the peak pairs with and without the chlorine atom. The effects become more evident with increasing chain length; shown most visually by the abundance ratios of the McLafferty rearrangement ions atm/z108/110 and 74, and fragments at m/z121/123 and 87.