N,N′-Bis(2-aminobenzyl)ethane-1,2-diaminium bis(4-methylbenzenesulfonate)

Abstract

The title salt, C16H24N4 2+·2C7H7O3S−, crystallizes with the dication situated on an inversion center and the anion in a general position. The cation contains two ammonium and two free amine groups, and the observed conformation for the chain linking the benzene rings is different from that found in the free tetra­amine and in the fully protonated tetra­amine. All amine and ammonium H atoms of the cation form hydrogen bonds with eight symmetry-related anions, using the sulfonate O atoms as acceptors. This arrangement for the ions precludes any π–π contacts between benzene rings in the crystal.

N,N′-Bis(2-aminobenzyl)ethane-1,2-diaminium dinitrate

“…However, the dication (C 16 H 24 N 4 ) 2+ presents a non-crystallographic inversion center, with the central aliphatic chain extended in the all-trans conformation. This conformation was previously obtained for the same cation crystallized as ptoluenesulfonate salt, although in that case, the dication was placed on a crystallographic inversion center (Garza Rodríguez et al, 2011). The free amine, for which the X-ray structure is also known (Rodríguez de Barbarín et al, 2007) has a different solid state conformation, although preserving the centrosymmetric character.…”

“…For the structure of the free neutral amine, see: Rodríguez de Barbarín et al (2007). For the p-toluenesulfonate salt of the title cation, see: Garza Rodríguez et al (2011). For related diammonium nitrate salts featuring R 4 4 (18) motifs, see: Liu et al (2007); Yang et al (2007).…”

N,N′-Bis(2-azaniumylbenzyl)ethane-1,2-diaminium tetrachloride

“…For the structure of the free tetraamine, see: Rodríguez de Barbarín et al (2007). For related structures, see: Gakias et al (2005); Garza Rodríguez et al (2009Rodríguez et al ( , 2011. For the synthesis of the title hydrochloride, see: Ansell et al (1983); Gruenwedel (1968).…”

“…In view of this behavior, it is important to characterize as many salts as possible, in order to avoid anions which are prone to compete with the macrocycle synthesis. Some cationic species formed from the above quoted tetraamine C 16 H 22 N 4 have been stabilized, for instance, with a mixture of nitrate and perchlorate (Garza Rodríguez et al, 2009) and with tosylate (Garza Rodríguez et al, 2011).…”