Potassium Phosphate, Tribasic → (3R)-tert-butyl 3-(6-(5-(5-chloro-2-fluoropyridin-3-yl)-1-(tetrahydro-2H-pyran-2-yl)-1H-indazol-3-yl)pyrazin-2-yloxy)piperidine-1-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

(3R)-tert-butyl 3-(6-(5-bromo-1-(tetrahydro-2H-pyran-2-yl)-1H-indazol-3-yl)pyrazin-2-yloxy)piperidine-1-carboxylate 10a (270 mg, 0.48 mmol), 5-chloro-2-fluoropyridin-3-ylboronic acid (97 mg, 0.56 mmol) (Combi-Blocks, Catalog# BB-3818), potassium phosphate tribasic (308 mg, 1.45 mmol) (Sigma-Aldrich, Catalog# P5629-25G, Lot#069K0110), dicyclohexyl(2′,4′,6′-triisopropylbiphenyl-2-yl)phosphine (13.8 mg, 0.03 mmol) (Strem, Catalog#15-1149, Batch# A0183078), and Pd2(dba)3 (13.3 mg, 0.02 mmol) (Strem, Catalog#46-3000, Lot# A8761089) were weighed into a 10 mL glass microwave vial. The vial was purged with argon, the solids were treated with dioxane (4 mL) and water (1 mL) and the vial was sealed. The contents were heated in Initiator microwave reactor (Personal Chemistry, Biotage AB, Inc., Uppsala, Sweden) at 115° C. for 30 min. The reaction mixture was treated with 2 mL of water and extracted with EtOAc (2×10 mL). The combined organic layers were dried over MgSO4, filtered and concentrated, affording (3R)-tert-butyl 3-(6-(5-(5-chloro-2-fluoropyridin-3-yl)-1-(tetrahydro-2H-pyran-2-yl)-1H-indazol-3-yl)pyrazin-2-yloxy)piperidine-1-carboxylate as a light yellow solid. MS (ESI, pos. ion) m/z: 609.2 (M+1). The material was used without purification. To a solution of (3R)-tert-butyl 3-(6-(5-(5-chloro-2-fluoropyridin-3-yl)-1-(tetrahydro-2H-pyran-2-yl)-1H-indazol-3-yl)pyrazin-2-yloxy)piperidine-1-carboxylate (292 mg, 0.48 mmol) in THF (2.2 mL) and EtOH (2.2 mL) was added HCl, 5-6N in IPA (0.8 mL, 26.40 mmol). The solution was heated in an oil bath at 65° C. for 1 h. The crude reaction was concentrated to a yellow solid that was dissolved in 5 mL of DMSO and purified on a reverse phase HPLC, using a gradient of 10-90% [0.1% TFA in ACN] in [0.1% TFA in water]. The desired fractions were collected, concentrated, and basified with 1 N NaOH, extracted with EtOAc. The EtOAc solution was washed with brine, dried with Na2SO4 and concentrated to afford (R)-5-(5-chloro-2-fluoropyridin-3-yl)-3-(6-(piperidin-3-yloxy)pyrazin-2-yl)-1H-indazole as an off white crystalline solid. MS (ESI, pos. ion) m/z: 425.1 (M+1).

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