In the title compound, C18H16, the [2.2]paracyclophane geometry is restrained to a considerable extent despite the introduction of the extra C = C bridge; typical paracyclophane features, such as the elongated C-C bridges, are still observed. However, the bridgehead atoms of the C C bridge are forced into unusually close proximity [2.657 (3) angstrom], which in turn causes the rings to be rotated to an interplanar angle of 13.7 (2)degrees. The packing involves hexagonally close-packed layers of molecules parallel to the xy plane, corresponding to the known '7,11' pattern of paracyclophanes, but without significant short intermolecular contacts.
In the title compound, C18H16, the [2.2]paracyclophane geometry is restrained to a considerable extent despite the introduction of the extra C = C bridge; typical paracyclophane features, such as the elongated C-C bridges, are still observed. However, the bridgehead atoms of the C C bridge are forced into unusually close proximity [2.657 (3) angstrom], which in turn causes the rings to be rotated to an interplanar angle of 13.7 (2)degrees. The packing involves hexagonally close-packed layers of molecules parallel to the xy plane, corresponding to the known '7,11' pattern of paracyclophanes, but without significant short intermolecular contacts.