Sunder N. Dhuri

1,3-Propanediammonium tetrathiotungstate and N,N,N',N'-tetramethylethylenediammonium tetrathiotungstate

The title complexes, (C(3)H(12)N(2))[WS(4)] and (C(6)H(18)N(2))[WS(4)], contain tetrahedral [WS(4)](2-) dianions, which accept a complex series of hydrogen bonds from the organic dications. The strength and number of these hydrogen bonds affect the W-S distances.

A novel hydrogen-bonded cyclic dibromide in an organic diammonium salt #

AbstractThe organic diammonium salt N,N′-dibenzyl-N,N,N′,N′-tetramethylethylenediammonium dibromide dihydrate, (dbtmen)Br2.2H2O (1), was prepared by the reaction of N,N,N′,N′-tetramethyl-ethylenediamine (tmen) with benzyl bromide.1 crystallizes in the triclinic space group

Synthesis, X-ray Structures, Spectroscopic and Thermal Characterization of Two New Organic Ammonium Tetrathiotungstates†

P\bar 1

On the Importance of H-Bonding Interactions in Organic Ammonium Tetrathiotungstates

with the following unit cell dimensions for C20H34Br2N2O2 (M = 494.31):a = 8.6672(6) Å,b = 11.7046(8) Å,c = 11.7731(8) Å, α = 76.988(8)°, β = 88.978(8)°, γ= 76.198(8)γ,V= 1129.26(13) Å3, Z=2. Three components, namely the (dbtmen)2+ dication, two bromide anions and two crystal water molecules constitute the structural arrangement of1. H2O molecules are linked to bromide anions via O-H...Br hydrogen bonding interactions resulting in the formation of a four-membered O2Br2 cyclic dibromide. The O2Br2 units and the dications are arranged as alternating layers extending in the crystallographicbc plane. The arrangement of anions and cations may be viewed as a typical lamellar structure. The crystal water molecules can be removed by heating 1 at 140°C and the anhydrous dibromide thus formed can be fully rehydrated as evidenced by IR spectra and X-ray powder patterns.

Crystallographic and thermal investigations of organic ammonium tetrathiomolybdates

Abstract Three new tetrathiomolybdates (pipH2)[MoS4] (1), (trenH2)[MoS4]·H2O (2) and [(prop)4N]2- [MoS4] (3) (pip = piperazine, tren = tris(2-aminoethyl)amine and prop = n-propyl) were synthesized and characterized by elemental analysis, infrared spectroscopy, single crystal X-ray crystallography, and thermoanalysis. All compounds were prepared by the base promoted cation exchange method, i.e. by the reaction of the ammonium salt of [MoS4]2− with the corresponding organic amine or organic ammonium hydroxide. In the compounds 1 and 2 the organic amines pip and tren are diprotonated and they are linked to the tetrahedral [MoS4]2− dianions through weak hydrogen bonding interactions. The strength and number of these hydrogen bonds affect the Mo-S bond lengths and a relatively long Mo-S bond of 2.2114(8) Å is observed in 1 while the longest Mo-S bond in 2 is 2.1951(5) Å . In compound 3 no S···H-N interactions are possible and the Mo-S bond lengths scatter in a more narrow range compared to those in compounds 1 and 2. The thermal behavior was investigated using differential thermal analysis and thermogravimetry. On heating compound 1 decomposes in two closely related steps while 2 loses first the crystal water followed by the decomposition of the tetrathiomolybdate. The final products are amorphous molybdenum sulfides. The decomposition of compound 3 yields a very porous material with sponge-like morphology.