1,2-DIHYDRO-8-METHYL-4(3H)-CARBAZOLONE PREPARED BY A NEW ARYNIC CYCLIZATION REACTION

Of the two possible keto-enol tautomeric species of the title compound , C13H13NO, it is the keto one that is found in the crystal; it involv es an intermolecular N-H...O double bond C hydrogen bond between molec ules, related by the 1/2 + x, 1/2 - y, 1/2 + z symmetry operation of t he P2(1)/n space group, which run in chains along the x axis. IR data of the solid product are assigned and it is deduced from the H-1 and C -13 NMR spectra that this hydrogen bond is also active in solution in DMSO. The relevant structural parameters of the molecule in the crysta l are compared with those calculated by molecular mechanics for the is olated structure.