Crystallographic and thermal investigations of organic ammonium tetrathiomolybdates

4-(2-Azaniumylethyl)piperazin-1-ium bis(perchlorate)

“…The organic molecule is doubly protonated at its primary and secondary N atoms, while the tertiary N atom, N2, remains unprotonated. Similar to the structures of some other 1-(2-ammoniumethyl)piperazinium salts (Guerfel et al, 1999;Srinivasan et al, 2008Srinivasan et al, , 2009, the piperazine ring adopts a chair conformation with the ethylammonium group occupying an equatorial position. In the crystal, the dicationic organic moieties and perchlorate anions are linked through N-H···O and C-H···O interactions (Table 1) into a three-dimensional supra-molecular network.…”

“…For the structures of related salts of the 4-(2-ammonioethyl)piperazin-1-ium cation, see: Guerfel et al (1999); Srinivasan et al (2008Srinivasan et al ( , 2009 Table 1 Hydrogen-bond geometry (Å , ). Symmetry codes: (i) Àx þ 1; Ày þ 1; Àz þ 1; (ii) x À 1 2 ; Ày þ 1 2 ; z À 1 2 ; (iii) x À 1; y; z; (iv) x À 1 2 ; Ày þ 1 2 ; z þ 1 2 ; (v) Àx þ 3 2 ; y À 1 2 ; Àz þ 1 2 ; (vi) Àx þ 1 2 ; y À 1 2 ; Àz þ 1 2 .…”

A spiral-like chain from a hydrogen-bonded cyclic dichloride containing a water dimer in a quaternary diammonium dichloride trihydrate

“…[11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] The simplest water cluster (H 2 O) 2 has been crystallographically characterized in the cavity of a cryptand, 25 and also in metal-organic framework materials. 26,27 During the course of our investigations of compounds derived from organic ammonium cations containing inorganic anions like tetrathiomolybdate [31][32][33] and tetrathiotungstate [34][35][36] we have identified a supramolecular water dimer in the crystal structure of a quaternary diammonium dichloride trihydrate (dbtmen)Cl 2 ⋅3H 2 O 1 (dbtmen is N,N′dibenzyl-N,N,N′,N′-tetramethylethylenediammonium) and these results are described in this paper.…”

“…It is to be noted that in the case of the corresponding bromide analogue the rehydration experiment was performed by equilibrating the anhydrous dibromide over water in a dessicator. 36 It is also noted that extended exposure times or equilibration over water of the anhydrous product does not result in the formation of any other product containing more than three moles of water. The TG-DTA experiment gave a very similar result and the thermogram (figure 5) exhibits endothermic events with a broad signal at around 128 o C and another signal at 156°C, which can be attributed to the dehydration of 1.…”

Synthesis and characterization of bis(alkylammonium) tetrasulfidometalates

“…As part of our research in this area, we are investigating the synthesis, spectral characteristics, thermal properties, and structural aspects of tetrasulfido compounds of Mo and W [6][7][8][9][10]. The research has resulted in a rich structural chemistry of the tetrahedral [MS 4 ] 2À (M ¼ Mo, W) compounds charge balanced by organic ammonium cations [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28].…”