2-Fluoro-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine

White to light yellow solid

To a solution of freshly distilled diisopropylamine (42.5 g, 0.42 mol) in diethyl ether was added n-butyllithium (2.5 M, 175 mL) under nitrogen atmosphere at 0 ° C and stirring was continued for 30 minutes. The system was cooled to -60 ° C and the ether solution of 2-fluoropyridine (34.0 g, 0.35 mol) was slowly added dropwise and the stirring was continued at -60 ° C for 1 hour. A solution of triisopropoxyborate (82.4 g, 0.44 mol) in diethyl ether was added dropwise, and the mixture was allowed to warm to room temperature and stirring was continued for 2 hours. A solution of pinacol (55.6 g, 0.47 mol) in diethyl ether was added dropwise over 10 minutes, followed by the addition of glacial acetic acid (22. lg, 0.37 mol). The reaction was stirred at room temperature overnight, filtered, and the filtrate was extracted with a 5percent aqueous solution of sodium hydroxide. With 3N hydrochloric acid slowly adjust the pH of the resulting aqueous phase to 6 ~ 7, keep the system temperature below 5 ° C, ethyl acetate extraction. The organic phase was collected and concentrated in vacuo to remove the solvent to give the desired product (27.0 g, 34percent).Step 8 : 2-fluoro-3-(4, 4, 5, 5-tetramethyl-l , 3, 2-dioxaborolan-2-yl)pyridineTo a solution of diisopropylamine (42.5 g, 0.42 mol) in THF (200 mL) was added n-BuLi (2.5 M, 175 mL) at 0°C under N3-Bromo-2-fluoropyridine (1.5 g, 8.52 mmol), potassium acetate (2.0 g, 21.30 mmol), bispinacolatodiboron (3.18 g, 13.21 mmol) and Pd(dppf)C12 (340 mg, 0.42 mmol) were taken in1, 4-dioxane (15 mL) and heated for 2 h at 90°C. The mixture was evaporated and used for nextstep without further purification (3.72 g).‘HNMR (400MHz, DMSO-d6): ö 8.36-8.35 (m, 1H), 8.20-8.15 (m, 1H), 7.37-7.35 (m, 1H), 1.35 (s, 12H). LCMS: 67percent, mlz = 224 (M+1) .3-Bromo-2-fluoropyridine (1.5 g, 8.52 mmol), potassium acetate (2.0 g, 21.30 mmol), bispinacolatodiboron (3.18 g, 13.21 mmol) and Pd(dppf)Cl2 (340 mg, 0.42 mmol) were taken in 1, 4-dioxane (15 mL) and heated for 2 h at 90° C.

Molecular Weight:223.05
Hydrogen Bond Acceptor Count:4
Rotatable Bond Count:1
Exact Mass:223.1179870
Monoisotopic Mass:223.1179870
Topological Polar Surface Area:31.4
Heavy Atom Count:16
Complexity:257
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes