Total synthesis of (12R)- and (12S)-12-hydroxymonocerins: stereoselective oxylactonization using a chiral hypervalent iodine(III) species

The first total syntheses of (12R)- and (12S)-12-hydroxymonocerins are described. The oxolane-fused isochroman-1-one framework is stereoselectively constructed via a double oxy-cyclization using a lactate-based chiral hypervalent iodine reagent. A catalytic variant of the double oxy-cyclization is also demonstrated using a chiral iodoarene as the precatalyst and m-CPBA as the co-oxidant.