4-(6-Chloro-4-(ethoxycarbonyl)chroman-7-yloxy)benzoic acid (Preparation 1) (51.6 mg, 0.137 mmol), in 1:1 DCM:DMF (0.1 M) was sequentially treated with 3-phenoxyphenethylamine (32.1 mg, 0.151 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (31.5 mg, 0.164 mmol), and 1-hydroxy-7-azabenzotriazole (5.59 mg, 0.0411 mmol) at ambient temperature. After 24 hours the reaction was applied directly to a silica gel column and eluted with a gradient (15% to 60%) of ethyl acetate-hexanes to provide the title compound (71.6 mg, 0.125 mmol, 91.4% yield) as a white solid.
