A Multifaceted Phosphate Tether: Application to the C15−C30 Subunit of Dolabelides A−D

Construction of the C15-C30 subunit of dolabelide utilizing a temporary phosphate tether is described. Two routes are reported that make use of the orthogonal protecting- and leaving-group properties innate to phosphate esters. One route relies on a selective terminal oxidation, while a second utilizes a CM/selective hydrogenation sequence. Both routes depend on a highly regio- and diastereoselective cuprate addition to set the requisite stereochemistry at C22.