The crystal structure of 4,12-dimethyl[2,2]metacyclophane

Abstract

The crystal is monoclinic, probably C2/c, with a= 12. 62, b=9.25, c=10"97 .~; [3=91.56 ; Z=4. The structure was determined from a three-dimensional Patterson synthesis, mad refined by differential syntheses. Allowance was made for thermal anisotropy. The two benzene rings are displaced stepwise, and distorted to a boat shape to avoid too close mutual contact. The methyl groups appear to be stationary, but may be in a condition of strongly hindered rotation.