Synthesis of Tetracyclic Heterocompounds as Selective Estrogen Receptor Modulators. Part 2. Process Improvement for Scale-Up Of 2,5,8-Substituted 11,12-Dihydro-5H-6,13-dioxabenzo[3,4]cyclohepta-[1,2-a]naphthalene Derivatives

An improved, reproducible nonchromatographic process for scale-up synthesis of 2,5,8-substituted 11,12-dihydro-5H-6,13-dioxabenzo[3,4]cyclohepta[1,2-a]naphthalene derivatives as selective estrogen receptor modulators (SERMs) is described. The titled compounds were prepared in 9−21% overall yield with high chemical purity (>97%) after nine consecutive synthetic steps.