Potassium Carbonate → 6-Chloro-5-(4-ethoxyphenyl)-1H-indazole-3-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 5-bromo-6-chloro-1H-indazole-3-carboxylic acid (100 mg, 0.36 mmol), 4-ethoxyphenylboronic acid (63.2 mg, 0.38 mmol), and 2 N aqueous potassium carbonate solution (1.10 mL, 2.18 mmol) in toluene (1.6 mL) and EtOH (2.4 mL) was degassed with N2 and treated with [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) dichloromethane adduct (29.4 mg, 0.036 mmol) under N2. The reaction mixture was sealed in a pressure tube and heated to 110° C. for 1 hour. The cooled reaction mixture was acidified to pH 5 and concentrated in vacuo. The resulting solid was purified by reverse phase HPLC (Column: Waters Sunfire C18 19×100, 5 μm; Mobile phase A: 0.05% TFA in water (v/v); Mobile phase B: 0.05% TFA in MeCN (v/v); 80.0% H2O/20.0% MeCN linear to 40.0% H2O/60.0% MeCN in 10.5 min, 40.0% H2O/60.0% MeCN linear to 0% H2O/100% MeCN in 0.5 min HOLD at 0% H2O/100% MeCN from 11.0 to 12.0 min. Flow: 25 mL/min) to give the title compound (5.3 mg, 5% yield). MS (ES+) 317.1 (M+H)+. Retention time=2.91 minutes (Column: Waters Atlantis dC18 4.6×50 mm, 5 μm; Mobile phase A: 0.05% TFA in water (v/v); Mobile phase B: 0.05% TFA in MeCN (v/v); Gradient: 95:5 A:B linear to 5:95 A:B in 4.0 min, hold at 5:95 A:B to 5.0 min. Flow: 2 mL/min).

Provenance & Evidence