Facile synthesis of optically active oxindoles by copper-catalyzed asymmetric monotosylation of prochiral 1,3-diols

A facile synthetic method toward optically active 3,3-disubstituted oxindoles with excellent enantioselectivity was achieved using chiral copper-catalyzed desymmetrization of prochiral 1,3-diols. The monotosylated product was transformed into oxindole derivatives efficiently.

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(R)-(+)-3-Hydroxymethyl-1-methyl-3-(p-toluenesulfonyloxymethyl)oxindoleC18H19O5NS[α]D22=+17.2 (c 1.0, CHCl3)Source of chirality: catalytic asymmetric monotosylationAbsolute configuration: (R)

(R)-(+)-3-Benzyloxymethyl-3-cyanomethyl-1-methyloxindoleC19H18N2O2[α]D22=+16.7 (c 0.36, CH2Cl2)Source of chirality: catalytic asymmetric monotosylationAbsolute configuration: (R)

(R)-(+)-3-((+)-10-Camphorsulfonyloxymethyl)-1-methyl-3-(p-toluenesulfonyloxymethyl)oxindoleC28H33O8NS2[α]D22=+24.0 (c 0.5, CHCl3)Source of chirality: catalytic asymmetric monotosylationAbsolute configuration: (R)