Reagents and conditions: (a) NaH, THF, 0 °C, 15 min; (b) SEMCl, 0 °C, 1 h; (c) NBS, MeCN, 0 °C → room temperature, 1 h; (d) sodium 4-(tert-butyl)benzenesulfinate, CuI, DMF, N2, 65 °C, 18 h; (e) NBS, MeCN, room temperature, 17 h; (f) (2,5-dimethoxyphenyl)boronic acid, Pd(dppf)Cl2, K2CO3, dioxane, H2O, N2, 100 °C, 6 h; (g) 2-methoxy-5-chlorophenylboronic acid, Pd(dppf)Cl2, K2CO3, dioxane, H2O, N2, 65 °C, 6 h; (h) NBS, MeCN, −30 °C → room temperature, 0.5 h; (i) sodium 4-(tert-butyl)benzenesulfinate, CuI, DMF, N2, 65 °C, 18 h.