International Union of Crystallography
Acta Crystallographica Section C
The title compound 5-acetyltricyclo[126.96.36.199,7]hexa-deca-4,6,10,12,13,15-hexaene, C18H18O,is the first example of a mono-π-substituted [2.2]paracyclophane to be structurally characterized. The average bending angles are α = 13.2 and β = 9.9°. The distance between the 'bottoms' of the practically parallel boat-like benzene nuclei is 3.098(2) Å. The π conjugation between the acetyl group and the substituted benzene cycle is negligible (rotation angle ca 45°) because of steric hindrance.