Sulfuric Acid → 6-Methoxy-3-(trichloromethyl)-2-benzofuran-1(3H)-one

Participants

Reaction Steps

A oven-dried 25 mL three neck round-bottomed flask containing a stirring bar was fitted with a drying tube (CaCl2) and was charged with m-methoxybenzoic acid (5.04 g, 17.91 mmol) followed by chloral hydrate (2.96 g, 17.91 mmol). Concentrated H2SO4 (12.0 mL) was added and the reaction mixture was left stirring at room temperature for 24 h. It was then poured onto ice, a thick precipitate formed and the mixture was left stirring vigorously until the ice was dissolved. The precipitate was filtered, washed with water and dried. The solid was recrystallised from ethanol, the crystals were then filtered and dried to yield 6-methoxy-3-(trichloromethyl)isobenzofuran-1(3H)-one as off-white needles (3.16 g, 63%). Spectral data for this compound were consistent with those in the literature. M.p. 134-136° C. (lit. m.p. 136-137° C.); 1H NMR (400 MHz, DMSO-d6): δ=7.88 (d, J=8.3 Hz, 1H), 7.49-7.39 (m, 2H), 6.54 (s, 1H), 3.90 (s, 3H).

Provenance & Evidence