Cesium carbonate → 1-(2-Morpholinoethyl)-1H-pyrazole-4-boronic acid pinacol ester

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (50 mg, 0.2 mmol), 4-(2-chloroethyl)morpholine hydrochloride (252 mg, 0.28 mmole, Aldrich, Cat. No. C42203), cesium carbonate (250 mg, 0.77 mmol) in acetonitrile (1 mL) in a sealed reaction vial was stirred at 90° C. overnight. LC/MS showed it worked well. After cooling it was diluted with ethyl acetate. Then the organic solution was washed with water, brine; dried over Na2SO4. After filtration the filtrate was concentrated to yield 50 mg of the product which was directly used in the next step reaction without further purification.

Provenance & Evidence