Molecular and crystal structures of 3-benzoyl-4-hydroxy-4-phenyl-(N-methyl)piperidine and 5-hydroxymethylene-4-phenyl-N-methyl-1,2,5,6-tetrahydropyridine

The crystal structures of two compounds—3-benzoyl-4-hydroxy-4-phenyl-(N-methyl)piperidine (I) orthorhombic crystals, space group P2₁2₁2₁, Z = 4] and 5-hydroxymethylene-4-phenyl-(N-methyl)-1,2,5,6-tetrahydropyridine (II) monoclinic crystals, space group P2₁/n, Z = 4]—are determined by X-ray diffraction. In I, the weak intermolecular OH?N hydrogen bonds link the molecules related by the a translation into homochiral chains. In II, the OH?N hydrogen bonds link the molecules into infinite homochiral chains twisting about the crystallographic screw axes 2₁(y). The helices are additionally strengthened by the short CH?O contacts.