ChemicalBook CAS DataBase List 3,6-Dihydro-2H-pyran-4-boronic acid pinacol ester

3,6-Dihydro-2H-pyran-4-boronic acid pinacol ester synthesis

7synthesis methods

Product Name:3,6-Dihydro-2H-pyran-4-boronic acid pinacol ester
CAS Number:287944-16-5
Molecular formula:C11H19BO3
Molecular Weight:210.08

73183-34-3

3,6-DIHYDRO-2H-PYRAN-4-YL TRIFLUORO-METHANESULFONATE

188975-30-6

3,6-Dihydro-2H-pyran-4-boronic acid pinacol ester

287944-16-5

To a 250 mL round-bottomed flask, a solution of 3,6-dihydro-2H-pyran-4-trifluoromethanesulfonate (2.7 g, 11.6 mmol), PdCl2(dppf) (440 mg, 0.6 mmol), and potassium acetate (3 g, 36 mmol) was added to a solution of dioxane (20 mL), which was subsequently displaced three times with argon to remove air. The reaction mixture was stirred at 80 °C overnight. Upon completion of the reaction, it was cooled to room temperature and filtered through a short column containing diatomaceous earth to remove solid impurities. The filtrate was concentrated under reduced pressure and the residue was purified by column chromatography (eluent: 10% dichloromethane solution of hexane) to give the final white solid product 3,6-dihydro-2H-pyran-4-boronic acid pinacol ester (2 g, 81% yield).

73183-34-3
586 suppliers
$6.00/5g

188975-30-6
67 suppliers
$88.00/1g

287944-16-5
233 suppliers
$7.00/250mg

Yield:287944-16-5 81%

Reaction Conditions:

with potassium acetate;(1,1'-bis(diphenylphosphino)ferrocene)palladium(II) dichloride in 1,4-dioxane at 80;

Steps:

63.2
A 250 ml_ round bottom flask containing trifluoro-methanesulfonic acid 3, 6- dihydro-2H-pyran-4-yl ester (2.7 g, 11.6 mmol), PdCI₂(dppf) (440 mg, 0.6 mmol) and potassium acetate (3g, 36 mmol) in dioxane (20 mL) was flushed with Ar three times. The reaction mixture was heated at 80 °C for overnight. After the reaction was cooled to room temperature, the reaction mixture was filter through a column packed with celite and the filtrate was concentrated. The residue was purified using column chromatography (10 % hexane in dichloromethane) and product was obtained as white solid (2g, 81 % yield).

References:

SCHERING CORPORATION WO2008/153858, 2008, A1 Location in patent:Page/Page column 307

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