1-Diazo-naphthalen-2(1H)-one.

The mol­ecule of the title compound, C10H6N2O, is nearly planar [maximum deviation = 0.030 (1) A]. The CN2 moiety is almost linear, with a C—N—N angle of 175.50 (14)°. A single inter­molecular C—H⋯O hydrogen bond is observed in the crystal structure. A π–π inter­action is also observed with the shortest distance being 3.6832 (12) A between the the centroids of the six-membered rings.