2-tert-Butyl-6-[(4-chloro-2-nitro-phen-yl)diazen-yl]-4-methylphenol.

In the title compound, C(17)H(18)ClN(3)O(3), the dihedral angle between the planes of the two benzene rings is 1.03 (7)°. The overall conformation of the mol-ecule is influenced, in part, by electron delocalization and by an intra-molecular bifurcated O-H⋯(O,N) hydrogen bonds. The O atoms of the nitro group, one of which serves as an H bond acceptor, are disordered over two sets of sites with refined occupancies of 0.56 (3) and 0.44 (3).