Asymmetric preparation of antifungal 1-(4′-chlorophenyl)-1-cyclopropyl methanol and 1-(4′-chlorophenyl)-2-phenylethanol. Study of the detoxification mechanism by Botrytis cinerea

Abstract

► The antifungal compound ( R )-1-(4′-chlorophenyl)-2-phenylethanol was prepared by means of treatment with ( R )-methyl oxazaborolidine, with >99% ee and 98% yield, and by lipase-mediated acetylation, with 99% ee . ► The antifungal compound ( S )-1-(4′-chlorophenyl)-2-phenylethanol was prepared by means of treatment with ( S )-methyl oxazaborolidine, with >99% ee and 98% yield, and by baker's yeast fermentation, with 97% ee . ► The antifungal compound ( R )-1-(4′-chlorophenyl)-1-cyclopropylmethanol was prepared by means of lipase-mediated hydrolysis, with 98% ee and 85.5% yield. ► The antifungal compound ( S )-1-(4′-chlorophenyl)-1-cyclopropylmethanol was prepared by means of baker's yeast fermentation, with 96% ee and 12% conversion. ► Biotransformation of 1-(4′-chlorophenyl)-1-cyclopropylmethanol by the phytopathogen Botrytis cinerea shows the detoxification pathways by the fungus. Chiral alcohols are important as bioactive compounds or as precursors to such molecules. On the basis of the different antifungal properties of the enantiopure alcohol derivatives of 4′-chlorophenyl cyclopropyl ketone and benzyl 4′-chlorophenyl ketone, their enantioselective synthesis by chemical and biocatalytic methods was studied. The detoxification pathways by the phytopathogen fungus Botrytis cinerea are reported.