Synthesis and crystal structures of two 1,3-di(alk-yloxy)-2-(methyl-sulfan-yl)imidazolium tetra-fluorido-borates.

Two salts were prepared by methyl-ation of the respective imidazoline-2-thione at the sulfur atom, using Meerwein's salt (tri-methyl-oxonium tetra-fluorido-borate) in CHCl. 1,3-Dimeth-oxy-2-(methyl-sulfan-yl)imidazolium tetra-fluorido-borate (), CHNOS·BF , displays a conformation of its two meth-oxy groups relative to each other whereas the two benz-yloxy groups present in 1,3-dibenz-yloxy-2-(methyl-sulfan-yl)imidazolium tetra-fluorido-borate (), CHNOS·BF , adopt an conformation. In the mol-ecules of and , the methyl-sulfanyl group is rotated out of the plane of the respective heterocyclic ring.

Synthesis and crystal structures of 2-bromo-1,3-di-methyl-imidazolium iodides.

Attempts at direct bromination of 1,3-di-methyl-imidazolium salts were futile. The title compounds, 2-bromo-1,3-di-methyl-imidazolium iodide chloro-form 0.33-solvate, CHBrN·I·0.

Crystal Structures of New Ammonium 5-Aminotetrazolates.

The crystal structures of three salts of anionic 5-aminotetrazole are described. The tetramethylammonium salt ([Formula: see text]) forms hydrogen-bonded ribbons of anions which accept weak C-H⋯N contacts from the cations. The cystamine salt (2/) shows wave-shaped ribbons of anions linked by hydrogen bonds to screw-shaped dications.