S(N)-2-TYPE MASS SPECTROMETRIC FRAGMENTATION IN SUBSTITUTED N-ALKYLPIPERIDINES .10. MASS SPECTROMETRY OF NITROGEN COMPOUNDS

An SN2‐type fragmentation was observed on mass spectrometric analysis of N‐(ω‐X‐alkyl)‐2‐alkylpiperidines (X = NRCOR′, CONH2, COOR, NH2). The molecular ion after loss of the 2 alkyl substituent on the piperidine ring may eject the neutral piperideine on attack of the substituent X on the α‐carbon of the N‐substituted alkyl‐chain. Through this process a cyclic fragment ion is formed. The influence of its ring size and of the substituent X on the stability of this fragment was investigated. The SN2 reaction is favoured in the case of production of five‐ and six‐membered rings. Copyright © 1968 Verlag GmbH & Co. KGaA, Weinheim