Stereoarrayed 2,3-Disubstituted 1-Indanols via Ruthenium(II)-Catalyzed Dynamic Kinetic Resolution-Asymmetric Transfer Hydrogenation.

Activated racemic 2,3-disubstituted 1-indanones 1 possessing two stereolabile centers were stereoselectively reduced to the corresponding chiral 2,3-disubstituted-1-indanols 2 by ruthenium(II)-catalyzed dynamic kinetic resolution-asymmetric transfer hydrogenation. In particular, this route offers a practical access to a new class of conformationally rigid enantiopure 1,4-diols 2k-m having four contiguous chiral centers. Transformation of ent-2k into a Pallidol analogue via a highly diastereo- and regioselective Friedel-Crafts benzylation of o-chloroanisole is presented.