Hydrochloric Acid → 6-Chloro-5-(4-(2-hydroxyethoxy)phenyl)-1H-indazole-3-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A suspension of 2-(4-bromophenoxy)ethanol (100 mg, 0.46 mmol), 5,5,5′,5′-tetramethyl-2,2′-bi-1,3,2-dioxaborinane (173 mg, 0.50 mmol), [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) (38.0 mg, 0.025 mmol) and potassium acetate (135 mg, 1.38 mmol) in 1,4-dioxane (1 mL) was sealed in a pressure tube and heated to 130° C. for 1 hour. To the mixture was added 5-bromo-6-chloro-1H-indazole-3-carboxylic acid (100 mg, 0.36 mmol), [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) (14.7 mg, 0.018 mmol), 2N aqueous potassium carbonate solution (0.5 mL, 1.0 mmol) and EtOH (2 mL). The mixture was sealed and heated to 130° C. for 1 hour. Water (3 mL) was added to the reaction mixture, followed by 1N HCl solution to adjust the pH to 2. The layers were separated and the aqueous layer was extracted with EtOAc (3×5 mL). The combined organic layers were dried over Na2SO4 and concentrated in vacuo. The crude material was purified by reverse phase HPLC (Column: Waters Sunfire C18 19×100 mm, 5 μm; Mobile phase A: 0.05% Formic acid in water (v/v); Mobile phase B: 0.05% Formic acid in MeCN (v/v); HOLD at 75.0% H2O/25.0% MeCN for 1.0 min. 75.0% H2O/25.0% MeCN linear to 45.0% H2O/55.0% MeCN in 6.75 min, linear to 0% H2O/100% MeCN to 7.0 min. HOLD at 0% H2O/100% MeCN from 7.0 to 8.0 min. Flow: 30 mL/min) to afford the title compound (23.1 mg, 15% yield). MS (ES+) 333.0 (M+H)+. Retention time=2.19 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