X-ray mapping in heterocyclic design: 16. X-ray diffraction study of 1-(4-chlorophenacyl)-4-methyl-1,5,6,7-tetrahydro-2<Emphasis Type="Italic">H</Emphasis>-cyclopenta[<Emphasis Type="Italic">b</Emphasis>]pyridin-2-one

The structure of 1-(4-chlorophenacyl)-4-methyl-1,5,6,7-tetrahydro-2H-cyclopentab]pyridin-2-one is studied using single-crystal X-ray diffraction. The structure (a = 37.006(8) Å, b = 8.967(3) Å, c = 27.911(3) Å, β = 96.52(2)°, Z = 24, space group P2₁/c) is solved by direct methods and refined to R₁ = 0.0608 and wR₂ = 0.1170. Six crystallographically independent molecules differ in the dihedral angle between the phenyl and heterocycle planes. The formation of Cl?Cl aggregates is discussed.