Acta Cryst. (2010). E66, o2656 [ doi:10.1107/S1600536810037748 ]
Abstract: In the crystal structure of the title salt, C22H21N2O6+·Br-·2H2O, pairs of betaine molecules are bridged by protons (the bridging proton is disordered), forming strong and symmetrical O-HO hydrogen bonds, leading to an infinite chain along the b axis. The water molecules are linked to the betaine molecule and the bromide ion through O-HO and O-HBr interactions. The central ring, located on an inversion centre, makes dihedral angles of 1.2 (2)° with the outer rings. One of the carboxylic acid groups is deprotonated.
Online 30 September 2010
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