N-H···S and C-H···S hydrogen bonds in two tetraalkylammonium dithiobiurea(1-) inclusion compounds.

Abstract

Two inclusion compounds of dithiobiurea and tetrapropylammonium and tetrabutylammonium are characterized and reported, namely tetrapropylammonium carbamothioyl(carbamothioylamino)azanide, C12H28N(+)·C2H5N4S2(-), (1), and tetrabutylammonium carbamothioyl(carbamothioylamino)azanide, C16H36N(+)·C2H5N4S2(-), (2). The results show that in (1), the dithiobiurea anion forms a dimer via N-H···N hydrogen bonds and the dimers are connected into wide hydrogen-bonded ribbons. The guest tetrapropylammonium cation changes its character to become the host molecule, generating pseudo-channels containing the aforementioned ribbons by C-H···S contacts, yielding the three-dimensional network structure. In comparison, in (2), the dithiobiurea anions are linked via N-H···S interactions, producing one-dimensional chains which pack to generate two-dimensional hydrogen-bonded layers. These layers accommodate the guest tetrabutylammonium cations, resulting in a sandwich-like layer structure with host-guest C-H···S contacts.