Stereoselective syntheses of rolliniastatin 1, rollimembrin, and membranacin.

A radical cyclization of beta-alkoxyvinyl sulfoxides-Pummerer rearrangement-allylation protocol was successfully applied to the synthesis of the threo/cis/threo/cis/erythro bis-oxolane moiety in rolliniastatin 1 (1), rollimembrin (2), and membranacin (3).

Asymmetric synthesis of secondary alcohols from primary alcohols via intramolecular carbenoid C-H insertion catalyzed by rhodium(II) 3-phenylcholestane-2-carboxylate.

Chiral secondary alcohols may be prepared from primary alcohols via asymmetric C-H insertion reactions of alpha'-alkoxy-alpha-diazoketones catalyzed by rhodium(II)(2R,3R)-3-phenylcholestane-2-carboxylate.