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 2N 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