Potassium Carbonate → (+/-)-6-Chloro-5-(4-(tetrahydrofuran-3-yl)phenyl)-1H-indazole-3-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 5,5,5′,5′-tetramethyl-2,2′-bi-1,3,2-dioxaborinane (110 mg, 0.32 mmol), oven dried potassium acetate (140 mg, 1.42 mmol), [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) dichloromethane adduct (27.0 mg, 0.033 mmol), and (±)-3-(4-bromophenyl)tetrahydrofuran (70.0 mg, 0.31 mmol) in 1,4-dioxane (3.1 mL) was degassed with N2 for 10 minutes, and subjected to microwave irradiation at 115° C. for 1 hour. The cooled reaction mixture was filtered through cotton and concentrated in vacuo to give a dark solid. To the dark solid was added 5-bromo-6-chloro-1H-indazole-3-carboxylic acid (75.0 mg, 0.270 mmol), 2N aqueous potassium carbonate solution (0.543 mL, 1.09 mmol) and [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) dichloromethane adduct (22.0 mg, 0.027 mmol). The reaction mixture was diluted with degassed toluene (0.8 mL) and EtOH (0.8 mL), and heated at 100° C. for 1.5 hours in a sealed tube. The cooled reaction mixture was concentrated in vacuo, and the residue was partitioned between 0.5N HCl (15 mL) and EtOAc (10 mL). The layers were separated and the aqueous layer was extracted with EtOAc (3×10 mL). The combined organic layers were dried over Na2SO4 and concentrated in vacuo. The resulting brown solid was purified by reverse phase HPLC (Column: Waters XBridge C18 19×100 mm, 5 μm; Mobile phase A: 0.03% NH4OH in water (v/v); Mobile phase B: 0.03% NH4OH in MeCN (v/v); 95.0% H2O/5.0% MeCN linear to 50.0% H2O/50.0% MeCN in 10.5 min, 50.0% H2O/50.0% 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 (9.6 mg, 10% yield). MS (ES+) 343.1 (M+H)+. Retention time=2.63 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