title: 2-Methyl-3-(4-nitro-phen-yl)acrylic acid.
abstract: The title compound, C(10)H(9)NO(4), forms R(2) (2)(8) dimers due to inter-molecular O-H⋯O hydrogen bonding in the crystal structure. Two dimers are further linked to each other through two inter-molecular C-H⋯O hydrogen bonds, forming an R(3) (3)(7) ring motif. The nitro groups form an intra-molecular C-H⋯O hydrogen bond mimicking a five-membered ring. As a result of these hydrogen bonds, polymeric sheets are formed. The aromatic ring makes a dihedral angle of 42.84 (8)° with the carboxyl-ate group and an angle of 8.01 (14)° with the nitro group. There is a π-inter-action (N-O⋯π) between the nitro group and the aromatic ring, with a distance of 3.7572 (14) Å between the N atom and the centroid of the aromatic ring.
authors.forename: Niaz
authors.initials: N
authors.lastname: Muhammad
authors.forename: M Nawaz
authors.initials: MN
authors.lastname: Tahir
authors.lastname: Zia-Ur-Rehman
authors.forename: Saqib
authors.initials: S
authors.lastname: Ali