Synthesis and crystal structure of bis-(2-phthal-imido-eth-yl)ammonium chloride dihydrate.

The title compound {systematic name: bis-[2-(1,3-dioxoisoindol-2-yl)eth-yl]aza-nium chloride dihydrate}, C20H18N3O4 +·Cl-·2H2O, is a phthalimide-protected polyamine that was synthesized by a previous method. It was characterized by ESI-MS, 1H NMR, and FT-IR. Crystals were grown from a solution of H2O and 0.1 M HCl. The central nitro-gen atom is protonated and forms hydrogen bonds with the chloride ion and a water mol-ecule. The two phthalimide units make a dihedral angle of 22.07 (3)°. The crystal packing features a hydrogen-bond network, two-coordinated chloride, and off-set π-π stacking.