SYNTHESIS AND STEREOCHEMICAL CHARACTERIZATION OF SOME OPTICALLY-ACTIVE 1,2-DINAPHTHYLETHANE-1,2-DIOLS

Three new diols, 1,2-di(2-naphthyl)ethane-1,2-diol, 1-(1-naphthyl)-2-(2-naphthyl)ethane-1,2-diol, and 1,2-di(1-naphthyl)ethane-1,2-diol, have been prepared in optically active form by catalytic asymmetric syn-dihydroxylation of the corresponding (E)-olefins. The complete stereochemical characterization was easily accomplished by transforming them into the corresponding isopropylidene ketals. These derivatives can be separated by HPLC on a Chiralcel OD column allowing the determination of the ee, and at same time, their CD spectra have been analyzed, allowing a safe assignment of absolute configuration in conjunction with molecular mechanics calculations and an exciton-coupling treatment.