Resolution and some properties of (1,1')-bi(dibenzofuranyl)-2,2'-diol (BIFOL)

Article abstract of DOI:10.1016/S0040-4020(97)00250-0

The resolution of C₂-symmetric (1,1')-bi(dibenzofuranyl)-2,2'-diol (BIFOL) is reported. Separation via recrystallisation of its 1:1 mixture of diastereomeric cyclic phosphoramidates by using (-)-(S)-1-phenylethylamine as chiral auxiliary gave both enantiomers in >98% enantiopurity and in good chemical yields. The configuration of BIFOL was determined by X-ray analysis of one of the diastereomeric phosphoramides. It is shown that the bidibenzofuran skeleton undergoes sulfonation reactions with high regioselectivity.