To a solution of (Z)-N-(1-(4-bromophenyl)-1-iodoprop-1-en-3-yl)sarcosine, tbutyl ester D (29.86 g, 64.06 mmol) in dimethoxyethane (300 mL) was added 3-thiopheneboronic acid (9.02 g, 70.47 mmol), Pd(PPh3)4 (3.70 g, 3.20 mmol), and 2M Na2CO3 (300 mL). The reaction was warmed to 90° C. with vigorous mechanical stirring for 4.5 hours. The mixture was cooled, and partitioned between EtOAc and water. The organic phase was washed with brine, dried (MgSO4), filtered, and concentrated. Column chromatography (2-5% acetone/hexanes) provided (Z)-N-(1-(4-bromophenyl)-1-(3-thienyl)prop-1-en-3-yl)sarcosine, tbutyl ester E(i) (27.06 g, 78%) as a yellow oil. 1H NMR (300 MHz, CDCl3) 1.43 (s, 9H), 2.36 (s, 3H), 3.14 (s, 2H), 3.28 (d, 2H), 6.16 (7, 1H), 6.86 (d, 1H), 7.12-7.14 (m, 3H), 7.32 (collapsed dd, 1H), 7.41 (d, 2H).
