Synthesis and structure of 9-methyl-1,10-di-hydro-pyrazolo-[3,4-a]carbazole

The title carbazole derivative, C₁₄H₁₁N₃, was prepared by reacting 1-hy-droxy-8-methyl-9H-carbazole-2-carbaldehyde with hydrazine hydrate. In the solid state, the fused-ring system is slightly puckered, the dihedral angle between the planes of the outer rings being 2.24 (7)°. In the crystal, mol-ecules are linked by {N-H}₂⋯N hy-dro-gen bonds to generate [010] chains, and weak C-H⋯π contacts consolidate the structure. A Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (43.1%), C⋯H/H⋯C (36.8%) and N⋯H/H⋯N (15.3%) inter-actions.