Carbon Dioxide → 4-Fluoro-3-methylbenzoic acid

Participants

Reaction Steps

A solution of 4-fluoro-3-methylphenylmagnesium bromide in THF (1.0 M, 250 mL, 250 mmol) was added in a stream over 5 min to a mixture of Dry Ice (10 g) in dry THF (250 mL), and the reaction was allowed to warm to RT and concentrated. The residue was partitioned between water (500 mL) and ether (250 mL), and the layers were separated. The aqueous layer was washed with ether (2×250 mL) and acidified to pH 1 with concentrated hydrochloric acid. The resulting mixture was cooled in an ice bath and filtered. The solid was washed with water and dried to afford the title compound (25.92 g, 67%) as an off-white solid: 1H NMR (400 MHz, CDCl3) δ 7.90-8.02 (m, 2H), 7.09 (t, J=8.9 Hz, 1H), 2.34 (d, J=1.7 Hz, 3H); IR (chloroform) 3400-2300 (broad), 1694 cm-1 ; MS(ES) m/e 155 [M+H+ ; m/e 153 [M-H]-.

Provenance & Evidence