1,3-Bis(2-methyl­prop-2-eno­yl)-1H-benz­imidazol-2(3H)-one

The mol­ecules of the title compound, C₁₅H₁₄N₂O₃, possesses crystallographically imposed twofold rotational symmetry, so the asymmetric unit contains one half-mol­ecule. The fused-ring system deviates significantly from planarity; the planes of the five- and six-membered rings are twisted with respect to each other by 3.0 (1)°. In the crystal, weak C—H...O hydrogen bonds link mol­ecules related by translation in [010] into chains.