1-Phenethylguanidinium Chloride

Abstract

The asymmetric unit of the title compound, C10H16N5+.Cl−, contains two molecules with quite different conformations of the biguanide moiety. The crystal structure determined by Herrnstadt et al. [J. Chem. Soc. Perkin Trans. 2 (1979), pp. 735–740] is properly refined, the H-atom positions on the biguanide moiety are evident and the hydrogen-bonding scheme is clarified. Protonation of the biguanide moiety produces a rearrangement of protons in this part of the molecule. The two independent protonated molecules in the crystal form a hydrogen-bonded dimer through two intermolecular N—H⋯N hydrogen bonds. In addition, the molecules are held together by van der Waals forces and several N—H⋯Cl intermolecular interactions.