SYNTHESIS OF TRIPHENYLENE 1,2-OXIDE (1,2-EPOXY-1,2-DIHYDROPHENYLENE) AND ABSOLUTE-CONFIGURATION OF THE TRANS-1,2-DIHYDRO DIOL METABOLITE OF TRIPHENYLENE - CRYSTAL-STRUCTURE OF (-)-(1R,2R)-TRANS-2-BROMO-1-MENTHYLOXYACETOXY-1,2,3,4-TETRAHYDROTRIPHENYLENE

The synthesis of triphenylene 1,2-oxide (1,2-epoxy-1,2-dihydrotriphenylene) (2) from both racemic and optically pure precursors is reported. Racemic triphenylene 1,2-oxide (2) was obtained in each case, in accord with PMO calculations which predict rapid racemization. Liver microsomal metabolism of both triphenylene (1) and racemic triphenylene 1,2-oxide (2) yielded predominantly the (-)-enantiomer (92 and 85%, respectively) of the trans-dihydro diol (5). The 1R, 2R configuration for (-)-(5) has been established by preparative h.p.l.c. separation of the dimenthyloxyacetate diasteroisomers of the dihydro diol (5) and stereochemical correlation to (-)-(1R,2R)-trans-2-bromo-1-menthyloxyacetoxy-1,2,3,4-tetrahydrotriphenylene (9A) whose absolute configuration has been assigned by X-ray crystallographic analysis.