CRYSTAL-STRUCTURES AND ENERGY REFINEMENT OF SOME 2,2'-DISUBSTITUTED BIPHENYL COMPOUNDS

Synthesis and structural determination by X-ray crystallography of thr ee substituted biphenyl structures are reported: (2) is monoclinic P2( 1)/n with a = 10.805(4), b = 8.079(3), c = 16.232(6) angstrom, beta = 100.96(5)-degrees: (4) is monoclinic P2(1)/n with a = 9.966(3). b = 10 ,007(3), c = 13.053(4) angstrom, beta = 96.74(5)-degrees (5) is tricli nic P1BAR with a = 12.033(5), b = 16.903(8), c = 9.752(4) angstrom, al pha = 94.70(3)-degrees, beta = 112.56(3)-degrees gamma = 76.12(3)-degr ees. In all compounds the biphenyl has two identical substituents in a n ortho position to the center inter-ring bond and present variable in ter-ring twist angles. In the process of investigating molecular geome try, we are interested in studying whether the calculated conformation s of our molecules can fit the crystallographic structures.