The Structure of 1,3-trans-Bis(4-chlorophenyl)-2,4-trans-di(4-pyridyl)cyclobutane, a Photodimer of 4'-Chloro-4-styrylpyridine

Article abstract of DOI:10.1107/S0567740880004773

The crystal structure of 1,3-trans-bis(4-chlorophenyl)-2,4-trans-di(4-pyridyl)cyclobutane, C26H20Cl2N2, has been determined from 1765 three-dimensional intensities, collected with an automated Philips PW 1100 four-circle single-crystal diffractometer and refined to R=0.058.Cell constans are a=16.307 (8), b=13.907 (2), c=9.666 (3) Angstroem, β=94.47 (5) deg, Z=4; the space group is P2₁/n.The cyclobutane ring has a puckered conformation, and the two dihedral angles are 19.1 and 19.2 deg.The structure determined shows that the dimerization process is a head-to-tail reaction.