The simple and efficient synthesis of lasofoxifene (4), a possible candidate for alleviating osteoporosis, via the novel three-component coupling reaction among 4- pivaloyloxybenzaldehyde (5), cinnamyltrimethylsilane (6), and anisole in the presence of HfCl 4 is illustrated. The successive cationic cyclization of the coupling product, olefin formation, and migration of the double-bond are performed to afford the common synthetic ...