CRYSTAL AND MOLECULAR-STRUCTURE OF NEWLY SYNTHESIZED IS(8'',11''-DIOXA[4.3.3]PROPELLA(3'',4''))BIPHENYL

The title compound 5 was obtained from 2,2',3,3'-tetramethylbiphenyl i n a multi-step reaction sequence leading to the bis(propellane). X-ray structure analysis proved the identity bis(propellane). In the solid state the molecule possesses roughly a twofold symmetry axis perpendic ular to the biphenyl bond. The conformation of the molecule is determi ned by a 53.5(1) torsional angle between the biphenyl planes. the prop ellane bond is parallel to the phenyl plane in both symmetric parts of the molecule, what implies a boat conformation of the fused six-membe red rings.