The synthesis and resolution of 2,2'-, 4,4'-, and 6,6'-substituted chiral biphenyl derivatives for application in the preparation of chiral materials

Various routes are examined for the synthesis of chiral biphenyl species that are substituted at the 2,2', 4,4' and 6,6' positions. An Ullmann coupling is employed on a dibrominated arene, which has occurred selectively at the more hindered bromine by virtue of the directing effect of an ortho ester substituent.