N-bromobutanimide → methyl 4-(4-bromo-1-methyl-1H-pyrazol-5-yl)-5-methyl-2-furancarboxylate

Participants

Reaction Steps

A solution of methyl 5-methyl-4-(1-methyl-1H-pyrazol-5-yl)-2-furancarboxylate (600 mg, 2.72 mmol)[prepared in Example 116] and N-bromosuccinimide (485 mg, 2.72 mmol) in tetrahydrofuran (13 ml) was stirred in a sealed tube for 1 h at 70° C. The reaction mixture was divided and half of the solution was 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 by column chromatography (5-15% EtOAc in hexanes yielding methyl 4-(4-bromo-1-methyl-1H-pyrazol-5-yl)-5-methyl-2-furancarboxylate (130 mg, 0.41 mmol, 15% yield) as an orange oil: LCMS (ES) m/e 299, 301 (M, M+2)+.

Provenance & Evidence