N-{3-[(2-Ammonioethyl)amino]propyl}ethane-1,2-diaminium tris(trifluoromethanesulfonate): a salt of a folded triply protonated tetramine

Abstract

The structure of a trifluoromethanesulfonate salt of a nontypical triply protonated linear tetramine, C(7)H(23)N(4)(3+).3CF(3)SO(3)(-), with a layered crystal structure is presented. One N atom remains unprotonated. The conformation of the cation is enforced by intra- and intermolecular hydrogen bonds. The crystal structure is built of ca 10 A deep layers, within which cations and anions are hydrogen bonded. Each layer is only weakly bound to its neighbours. This study shows a rare example of an unsymmetrically protonated polyamine and the relation between the lack of protonation, intramolecular hydrogen bonding and the conformation of the cation.

Fluorinated mixed valence Fe(ii)–Fe(iii) phosphites with channels templated by linear tetramine chains. Structural and magnetic implications of partial replacement of Fe(ii) by Co(ii)

“…In the Cambridge Structural Database (CSD) there are only three structures, based on ionic salts, containing uncomplexed N,N′-bis(2-aminoethyl)-1,3-propanediamine. In two of them, the molecule is a tetracation 49 and in the other, a trication, 50 with gttttttg (g indicates gauche and t trans) and gttggggt conformations, respectively. In the studied compounds, the existence of the symmetry centre forces the splitting of the central carbon (C4) into two positions producing conformers A and B with conformations not previously seen in the mentioned structures.…”

N,N′-Bis(2-ammonioethyl)propane-1,3-diaminium tris(perchlorate) chloride

“…In the Cambridge Structural Database (CSD, Version 5.30 of November 2008; Allen, 2002) there are only two structures of uncomplexed N,N 0 -bis(2-aminoethyl)propane-1,3-diamine, one a tetracation (with benzene-1,2,4,5-tetracarboxylate; Su et al, 2002) and one an uncommon trication [with tris(trifluoromethanesulfonate); Patroniak et al, 2008]. Their conformations differ substantially: while the tetracation is gttttttg (g denotes gauche and t trans), in the trication an intramolecular N-HÁ Á ÁN hydrogen bond enforces a more complicated gttggggt conformation.…”