Crystal structure of 2,6-diphenyl-3-methyl-N-nitrosopiperidin-4-one

The structure of the 2,6-diphenyl-3-methyl-N-nitrosopiperidin-4-one (C18H18N2O2) has been investigated in solution and in the solid state by IR, NMR and X-ray methods. The crystal belongs to the monoclinic space group P21/n with a = 7.7134(6), b = 14.7754(14), c = 27.321(3) Å and β = 94.617(3)°. In crystal structure, the piperidine ring adopts a boat conformation with a slight distortion. One of the phenyl groups is in axial orientation, while the other phenyl and methyl groups are in equatorial orientations.