Pinacol → 5-(1,3-Dioxolan-2-yl)-2-fluoro-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine

Beteiligte Stoffe

Reaktionsschritte

5-(1,3-Dioxolan-2-yl)-2-fluoropyridin-3-ylboronic acid (14.56 g, 68.4 mmol) was suspended in PhMe (300 mL) and anhydrous magnesium sulfate (41.223 g, 342 mmol) and pinacol (8.27 g, 70.0 mmol) were added. The reaction was stirred under nitrogen at room temperature over the weekend. The suspension was filtered, and the solid was washed with EtOAc. The filtrate was washed with brine (2×200 mL), and the organic phase was dried over sodium sulfate, filtered, concentrated and dried to give 19.19 g of 5-(1,3-dioxolan-2-yl)-2-fluoro-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine as a light yellow powder. 1H NMR (CDCl3, 400 MHz) δ 8.39 (d, J=2.54 Hz, 1H); 8.28 (dd, J=8.02 Hz, 2.54 Hz, 1H); 5.84 (s, 1H); 4.17-4.04 (m, 4H); 1.37 (s, 12H).

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