2-Methyl-2-butene → 1-(2-Bromopyridin-4-yl)cyclopropane-1-carboxylic acid

Participants

Reaction Steps

A solution of sodium chlorite (368 mg, 3.26 mmol) and sodium dihydrogen phosphate monohydrate (449 mg, 3.26 mmol) in 5 mL of water is added dropwise to a solution of crude 1-(2-bromo-pyridin-4-yl)-cyclopropanecarbaldehyde (566 mg, 2.50 mmol) and 2-methyl-2-butene (1.73 mL, 16.3 mmol) in tert-butanol (12 mL), and the resulting reaction mixture is stirred at room temperature. After 18 hours, the mixture is concentrated in vacuo, acidified to pH 2 with 1M aqueous solution of HCl, diluted with brine (25 mL) and extracted with ethyl acetate (3×50 mL). The combined organic layers are dried over Na2SO4, filtered and concentrated to afford crude 1-(2-bromo-pyridin-4-yl)-cyclopropanecarboxylic acid, which is used without purification.

Provenance & Evidence