Our first major challenge in this synthesis was installation of the all-syn stereotriad of 5. We hypothesized that diastereoselectivity in this conjugate addition may be achievable if addition were directed by the unprotected homoallylic alcohol of 3. There is literature precedent for diastereoselectivity in conjugate additions in which an allylic alcohol serves as a stereocontrol element, but, to our knowledge, very little is known about chelation to a homoallylic alcohol. Accordingly, many conditions were tested (Figure ). Early experiments with organocuprates yielded intractable mixtures of diastereomers. A positive result came upon switching to organoaluminum reagents, prepared from reaction of the corresponding Grignard reagent with AlCl3. With three equivalents of tri((Z)-prop-1-en-1-yl)aluminum, we isolated desired product in 10% yield, but, more importantly, as a single diastereomer (Figure , Entry 1).