1-Aza-niumyl-cyclo-butane-1-carboxyl-ate monohydrate.

ABSTRACT

In the title compound, C5H9NO2·H2O, the amino acid is in the usual zwitterionic form involving the α-carboxyl-ate group. The cyclo-butane backbone of the amino acid is disordered over two conformations, with occupancies of 0.882 (7) and 0.118 (7). In the crystal, N-H⋯O and O-H⋯O hydrogen bonds link the zwitterions [with the water molecule involved as both acceptor (with the NH3 (+)) and donor (through a single carboxylate O from two different aminocyclobutane carb-oxylate moities)], resulting in a two-dimensional layered structure lying parallel to (100).