To a solution of (rac)-2-(4-(4-(trifluoromethyl)phenyl)-6,7-dihydro-5H-cyclopenta[c]pyridin-7-yloxy)acetic acid hydrochloride (example 99) (34.6 mg, 0.093 mmol) in DMF (1 mL) was added N,N-triethylamine (31 μL, 0.22 mmol) and 1,1′-carbonyldiimidazole (18.0 mg, 0.11 mmol). The reaction was stirred at room temperature for 2 h, cooled (0°) and treated with aq. 25% ammonia solution (0.87 mL, 5.55 mmol) and evaporated after 30 min to give a 1:1 mixture of starting material and product. The residue was dissolved in CH2Cl2, dried (Na2SO4) and evaporated. The oil was again dissolved in DMF (1 mL) and N,N-triethylamine (15.5 μL, 0.11 mmol) and 1,1′-carbonyldiimidazole (18.0 mg, 0.11 mmol) were added. The reaction was stirred at room temperature for 2 h, cooled (0°) and treated with aq. 25% ammonia solution (0.87 mL, 5.55 mmol) and evaporated after 30 min at room temperature. The solution was evaporated, dried in vacuo and purified by flash chromatography (20 g SiO2, Telos-cartridge, 3% MeOH in CH2Cl2) to give the title compound (15 mg, 48%) as off-white solid. MS: 337.1 (M+H+).
