N-(2,5-Dichloro-phen-yl)maleamic acid.

The asymmetric unit of the title compound, C(10)H(7)Cl(2)NO(3), contains two independent mol-ecules. The mol-ecular conformation of each maleamic unit is stabilized by an intra-molecular O-H⋯O(carbon-yl) hydrogen bond owing to the anti disposition of the participating entities. The mean planes through the benzene ring and the amido group are inclined at angles of 45.7 (1) and 40.8 (1)° in the two mol-ecules. In the crystal, the independent mol-ecules self-associate via N-H⋯O hydrogen bonds into zigzag ribbons propagating along the a axis. The ribbons are weakly coupled by C-H⋯π and C-H⋯O inter-actions.