Encapsulation and selective recognition of sulfate anion in an azamacrocycle in water

Structural characterization of a sulfate complex with an azamacrocycle suggests that one sulfate is encapsulated in the macrocyclic cavity with eight hydrogen bonds; a significant selectivity of the host was observed for sulfate over halides, nitrate and perchlorate as evaluated by 1H NMR studies in water

Tris(2-benzamido­eth­yl)ammonium tetra­fluoro­borate

In the title compound, C27H31N4O3 +·BF4 −, the central N atom is protonated. The three arms form a pocket and one amidic O atom accepts an inter­molecular hydrogen bond with the protonated amine. The tetra­fluoro­borate anion is outside the cavity and is hydrogen bonded to one amide N atom. Adjacent organic cations are connected by a pair of N—H⋯O hydrogen bonds, forming a chain