o-DPPB-Directed Stereoselective Conjugate Addition of Organocuprates

Substrate-directed diastereoselective conjugate addition of Gilman cuprates to acyclic enoates has been achieved with the aid of the substrate-bound reagent-directing o-DPPB-group (o-DPPB=ortho-diphenylphosphanyl benzoate). Combining o-DPPB-directed hydroformylation with the o-DPPB-directed cuprate addition provides access to building blocks with up to four stereogenic centers, which may be of relevance for polyketide synthesis. Limit and scope of the o-DPPB-directed cuprate addition of Gilman cuprates with respect to enoate structure as well as control experiments which probe the role of the o-DPPB group are reported.