General procedure for the synthesis of 3-(3-iodophenyl)acrylic acid from (E)-3-(3-bromophenyl)acrylic acid: CuI (9.6 mg, 0.050 mmol, 5.0 mol%), (E)-3-(3-bromophenyl)acrylic acid (228 mg, 1.00 mmol), NaI (300 mg, 2.00 mmol), evacuated and replaced three times with argon. A dioxane solution (1.0 mL) of racemic trans-N,N'-dimethyl-1,2-cyclohexanediamine (16 μL, 0.10 mmol, 10 mol%) and 1,1,1,3,3,3-hexamethyldisilazane (211 μL, 1.00 mmol) was added under argon protection. The Schlenk tube was sealed with a PTFE valve and the reaction mixture was stirred at 110 °C for 22 hours. Upon completion of the reaction, the suspension was cooled to room temperature, poured into ether (20 mL) and washed with a 10% aqueous hydrochloric acid solution of Na2S2O5 (3 x 20 mL). The organic phase was dried with anhydrous Na2SO4 and concentrated under reduced pressure. The residue was dissolved in hot ethanol (5 mL), hot water (5 mL) was added, and crystallized at 0°C for 15 h. 3-(3-Iodophenyl)acrylic acid (256 mg, 93% yield) was obtained as light yellow needle-like crystals. Melting point: 186-188 °C (literature values 180-182 °C, see Yuzikhin, O. S.; Vasil'ev, A. V.; Rudenko, A. P. Russ. J. Org. Chem. 2000, 36, 1743).1H NMR (400 MHz, DMSO-d6): δ 12.47 (s, 1H) ): δ 12.47 (s, 1H), 8.08 (s, 1H), 7.77 (d, J = 7.8 Hz, 1H), 7.72 (d, J = 7.8 Hz, 1H), 7.52 (d, J = 16.0 Hz, 1H), 7.22 (t, J = 7.8 Hz, 1H), 6.58 (d, J = 16.0 Hz, 1H).13C NMR (100 MHz, DMSO-d6 ): δ 167.3, 142.3, 138.6, 136.6, 136.5, 130.9, 127.4, 120.6, 95.4.
