Pyrrolidinium-2-carboxylate-4-nitrophenol (1/2)

In the title compound, C5H9NO2 center dot 2C(6)H(5)NO(3), the pyrrolidine ring of the pyrrolidinium-2-carboxylate zwitterion adopts a twisted conformation on the -CH2-CH2-bond adjacent to the N atom. The mean plane of this pyrrolidine ring forms dihedral angles of 25.3 (3) and 32.1 (3)degrees with the two nitrophenol rings. An intramolecular N-H center dot center dot center dot O hydrogen bond occurs in the pyrrolidinium-2-carboxylate molecule. In the crystal, molecules are linked via O-H center dot center dot center dot O and N-H center dot center dot center dot O hydrogen bonds, enclosing R-3(2)(8) ring motifs, forming chains running parallel to the a axis. These chains are further crosslinked by O-H center dot center dot center dot O and C-H center dot center dot center dot O hydrogen bonds, forming undulating two-dimensional networks lying parallel to (001).