Reaction Steps
Racemic iodide 12i (355 mg, 1.00 mmol), 2-bromophenylboronic acid (210 mg, 1.05 mmol) and Pd(PPh3)4 (115 mg, 0.10 mmol) were added to a dry Schlenk flask, followed by DME (10 mL) and an aqueous solution of 3 M aqueous NaOH (0.50 mL, 1.50 mmol). Argon was bubbled through the resulting mixture for 10 minutes, and the system was heated at reflux for 15 h. The reaction mixture was allowed to cool to room temperature, diluted with Et2O, washed with water (1×5 mL), brine (1×5 mL), dried over Na2SO4, filtered, and all volatiles were removed in vacuo. Gradient flash column chromatography (silica gel, 97:3→95:5 t-BuOMe/hexane) afforded 58 (177 mg, 46%) as an orange oil: Rf 0.38 (90:10 hex/EtOAc); IR (KBr, CHCl3) vmax 3091, 2947, 2846, 2783, 1587, 1502, 1485, 1416 cm−1; 1H NMR (300 MHz, CDCl3) δ 8.12 (dd, 1H, J=7.7, 1.5 Hz), 7.26 (dd, 1H, J=8.1, 1.2 Hz), 7.34 (td, 1H, J=7.5, 1.2 Hz), 7.13 (td, 1H, J=7.8, 1.8 Hz), 4.32 (s, 5H), 4.13 (t, 1H, J=1.8 Hz), 4.10-4.05 (m, 2H), 2.41 (s, 6H); 13C NMR (75 MHz, CDCl3) δ 157.5, 132.6, 127.5, 127.0, 120.0, 113.1, 110.5, 75.5, 68.9, 66.8, 62.0, 56.8, 55.6, 44.1; EIMS [m/z (%)] 385 (81Br M+, 91), 383 (79Br M+, 100), 182 (62); HRMS (EI) calcd for C18H18N56Fe79Br: 382.9972. Found 382.9974.
