ChemicalBook CAS DataBase List 2-Fluoropyridine-4-boronic acid

2-Fluoropyridine-4-boronic acid synthesis

4synthesis methods

Product Name:2-Fluoropyridine-4-boronic acid
CAS Number:401815-98-3
Molecular formula:C5H5BFNO2
Molecular Weight:140.91

5419-55-6
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$12.00/5g

128071-98-7
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$7.00/1g

401815-98-3
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$10.00/250mg

Yield:401815-98-3 91%

Reaction Conditions:

with n-butyllithium in tetrahydrofuran;hexane;toluene at -78; for 1 h;Inert atmosphere;

Steps:

A.1
[00178] Step 1 : To a solution of anhydrous toluene and tetrahydrofuran ("THF") (4:1, 250 mL) were added 4-bromo-2-fluoropyridine 1 (30.0 g, 0.17 mol) and triisopropyl borate (38.4 g, 0.20 mol). The mixture was cooled to -78 °C under a nitrogen atmosphere. Then, n- butyllithium (80 mL, 0.20 mol) (2.5 M in hexanes) was added dropwise over 30 minutes, followed by stirring at the same temperature for an additional 30 minutes. The mixture was finally warmed up to -20 °C over 1 hour. Thin layer chromatography ("TLC") (petroleum ether ("PE"):ethyl acetate ("EtOAc") = 1 :1) indicated that the starting material was consumed. The reaction mixture was acidified to a pH of 2 with 3N HCl (50 mL) and then stirred at room temperature for 15 minutes. The mixture was partitioned between EtOAc (150 mL) and water (150 mL). The organic layer was isolated, washed with water, brine, dried over anhydrous MgS0₄, then filtered and evaporated to provide (2-fluoropyridin-4-yl)boronic acid (22.0 g, 91%) as a solid.

References:

ARRAY BIOPHARMA INC.;GENENTECH, INC.;BLAKE, James, F.;COOK, Adam;GAUDINO, John;GUNAWARDANA, Indrani, W.;HICKEN, Erik, James;HUNT, Kevin, W.;LYON, Michael;METCALF, Andrew, T.;MOHR, Peter, J.;MORENO, David, A.;NEWHOUSE, Brad;REN, Li;SCHWARZ, Jacob;CHEN, Huifen;GAZZARD, Lewis;SCHMIDT, Jane;DO, Steve WO2015/103137, 2015, A1 Location in patent:Paragraph 00178

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5419-55-6
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$12.00/5g

22282-70-8 Synthesis