Ethyl 2-amino-4,5-dimethylthiophene-3-carboxylate

In the title compound, C9H13NO2S, the mean planes of thiophene ring [maximum deviation = 0.0042 (10) angstrom] and ethoxycarbonyl group [0.0242 (15) degrees] are almost coplanar [dihedral angle between them = 0.68 (11)degrees]. The H atoms of the two methyl groups attached to the thiophene ring are each disordered over two orientations with site-occupancy ratios of 0.77 (4): 0.23 (4) and 0.84 (4): 0.16 (4). An intramolecular NH center dot center dot center dot O hydrogen bond generates an S(6) ring motif. In the crystal, molecules are linked by N-H center dot center dot center dot O hydrogen bonds into an infinite wave-like chain running parallel to the b-axis direction. The crystal structure also features C-H center dot center dot center dot pi interactions.