To a solution containing 2-(4-fluorophenyl)-5-methoxybenzo[b]thiophene-3-carboxylic acid (0.57 g, 1.9 mmol), HOAT (0.28 g, 2.1 mmol), diisopropylethylamine (2.3 mL, 13.2 mmol), methylamine hydrochloride (0.20 g, 2.8 mmol) and dichloromethane (20 mL) was added EDCI (0.51 g, 13.2 mmol). The solution was maintained at room temperature for 6 h, diluted with additional DCM (20 mL), washed with water (20 mL), washed with aqueous HCl (2×20 mL, 0.1 N), dried over MgSO4, filtered and concentrated to afford 2-(4-fluorophenyl)-5-methoxy-N-methylbenzo[b]thiophene-3-carboxamide which was used without further purification. 1H NMR (500 MHz, DMSO-D6) δ ppm 8.30 (d, J=4.27 Hz, 1H), 7.90 (d, J=8.85 Hz, 1H), 7.60 (dd, J=8.70, 5.34 Hz, 2H), 7.34 (t, J=8.85 Hz, 2H), 7.16 (d, J=2.14 Hz, 1H), 7.07 (dd, J=8.85, 2.44 Hz, 1H), 3.81 (s, 3H), 2.74 (d, J=4.58 Hz, 3H). LCMS: retention time: 2.513 min. LC data was recorded on a Shimadzu LC-10AS liquid chromatograph equipped with a Phenomenex-Luna, 10 micron, C18, 4.6×50 mm column using a SPD-10AV UV-Vis detector at a detector wave length of 220 nM. The elution conditions employed a flow rate of 4 mL/min, a gradient of 100% solvent A/0% solvent B to 0% solvent A/100% solvent B, a gradient time of 4 min, a hold time of 1 min, and an analysis time of 5 min where solvent A was 5% CH3CN/95% H2O/10 mM ammonium acetate and solvent B was 5% H2O/95% CH3CN/10 mM ammonium acetate. MS data was determined using a Micromass Platform for LC in electrospray mode. m/z 316 (MH+).
