Three fluoroalkylated derivatives (1–3) of the selective estrogen receptor modulator (SERM), raloxifene, have been synthesized. The key step in the synthesis is the C–C bond formation of benzo [b] thiophene and a substituted phenyl group (ring C) using a Stille reaction. The in vitro binding affinities of the substituted raloxifenes 1–3 are 45, 60, 89%, respectively, relative to the affinity of estradiol, which is higher than the affinity of raloxifene itself (25%). ...