Mass Spectrometry of Some Saturated Heterocycles

a-cleavage a-methylene group a-ring-cleft acyclic aliphatic aliphatic sulphoxides alkene amines amines and sulphides base-peak Basic fragmentation processes butanol C-S fission C2H5 ions carbon-heteroatom celite CH3SO CHARACTERISTIC FRAGMENTS CHCH Chem cleft molecular ion Compound D-content cyclic amines cyclic compounds cyclic sulphoxides DBSO decomposes further decomposition deuterated analogues deuterium Deuterium labelling di-n-butyl sulphoxide DBSO Djerassi DPeSO2 Duffield ethers and sulphides ethylene expulsion fragment ions fragment m/e H-migr HeMNH HeMO HeMS heterocycles hydrogen atom hydrogen migration hydrogen scrambling hydrogen transfer imine intensity involving ion m/e LiAlD4 loss of OH M-OH m/e Figs Mass spectra Mass Spectrometry Mc Lafferty rearrangement metastable transitions methyl mole n-butyl sulphone n-butyl sulphoxide n-CH nitrogen nonspecific obtained oxide oxygen peak shift data PeMNH PeMO PeMS PeMSO2 polymethylene radical position ratio rearrangement processes Scheme seven-membered ring SO₂H species spectrum sulphides sulphoxides and sulphones Table TeMNH TeMO TeMS tetrahydrofuran tetrahydrothiophene y-H-migr y-hydrogen yield α α