text: The cladiellin family of marine natural products possesses interesting molecular architecture, generally containing a 9-membered medium-sized ring. The synthesis of (−)-cladiella-6,11-dien-3-ol  allowed access to a variety of other members of the cladiellin family.  Notably, the conversion to cladiell-11-ene-3,6,7-triol makes use of macrocyclic stereocontrol in the dihydroxylation of a trisubstituted olefin.  Below is shown the synthetic step controlled by the ground state conformation of the macrocycle, allowing stereoselective dihydroxylation without the usage of an asymmetric reagent. This example of substrate controlled addition is an example of the peripheral attack model in which two centers on the molecule are added two at once in a concerted fashion.