2-(4-Chloro-3,3,7-trimethyl-2,3-dihydro-1H-indol-2-yl­idene)-2-cyano­acetamide

Reaction of 2-(4-chloro-3,3,7-trimethyl-2,3-dihydro-1H-indol-2-yl­idene)propane­dial with hydroxyl­amine gives the title compound, C(14)H(14)ClN(3)O, in which the ring N atom is essentially planar [sum of angles around the ring N atom = 361°], indicating conjugation with the 2-cyano­acryl­amide unit. The orientation of the acetamide group arises from intra­molecular hydrogen bonding between the indole N—H and carbonyl groups. In the crystal, inversion-related acetamide groups form N—H⋯O hydrogen-bonded dimers in graph-set R (2) (2)(8) motifs, whilst dimers are also formed by pairs of amine–nitrile N—H⋯N hydrogen bonds in R (2) (2)(12) motifs. These inter­actions together generate ribbons that propagate along the b-axis direction.