Triethylamine → 1-methoxy-3-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazol-1-yl)propan-2-ol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a stirred solution of pyrazole-4-boronic acid pinacol ester (0.25 g, 1.29 mmol) in THF (5 mL) was added a solution of sodium bis(trimethylsilyl)amide (0.71 mL, 2M in THF, 1.42 mmol), followed by 1-chloro-3-methoxy-2-propanol (0.24 g, 2.58 mmol). The reaction mixture was stirred in a sealed vial at 90° C. for 6 days. Additional 1-chloro-3-methoxy-2-propanol (0.24 g, 2.58 mmol) was added, followed by triethylamine (0.35 mL, 2.60 mmol). The reaction mixture was stirred at 90° C. for 3 days, then cooled to r.t. Water (2 mL) and EtOAc (5 mL) were added. The organic fraction was separated, washed with H2O (2×2 mL), then brine (2 mL), dried (MgSO4), filtered and concentrated in vacuo to give the title compound (0.38 g, 96%) as an orange oil that was used without further purification. LCMS (ES+) 283.0 (M+H)+, RT 2.52 minutes (Method 1).

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