Photoelectron Spectroscopic Studies of Piperidine and its N-Halo Derivatives

Abstract

The He_I photoelectron spectra of N-chloropiperidine and N-bromopiperidine have been measured and compared with that of piperidine. The ionization energies associated with the nitrogen lone- pair and halogen non-bonding electrons indicate that there is considerably less n_N-n_x resonance interaction than in the smaller halo amines. He_II studies show that the halogen character is localized in both the N-halopiperidines with most ionization energies showing simple inductive shifts resulting from halogenation.