Potassium Carbonate → methyl 5-methyl-4-{1-methyl-4-[(1Z)-1-propen-1-yl]-1H-pyrazol-5-yl}-2-thiophenecarboxylate

Participants

Reaction Steps

A solution of methyl 4-(4-bromo-1-methyl-1H-pyrazol-5-yl)-5-methyl-2-thiophenecarboxylate (320 mg, 1.015 mmol)[prepared in Example 99], potassium carbonate (702 mg, 5.08 mmol), bis(tri-t-butylphosphine)palladium(0) (25.9 mg, 0.05 mmol) and (1Z)-1-propen-1-ylboronic acid (87 mg, 1.01 mmol) in 1,4-dioxane (5.3 ml) and water (1.3 ml) was stirred at 80° C. in a sealed tube for 12 h. The reaction contents were partitioned between H2O-DCM and the aqueous phase was washed several times with DCM. The combined organic fractions were dried over Na2SO4, concentrated and purified via column chromatography (10-50% EtOAc in hexanes) affording methyl 5-methyl-4-{1-methyl-4-[(1Z)-1-propen-1-yl]-1H-pyrazol-5-yl}-2-thiophenecarboxylate (243 mg, 0.88 mmol, 87% yield) as a yellow oil: LCMS (ES) m/z=277 (M+H)+.

Provenance & Evidence