Sulfuric Acid → HCID 9861204, compound

Participants

Reaction Conditions

Reaction Steps

To a mixture of 2-methoxyphenyl methanesulfonate (Example 50b) (82 g, 406.4 mmol) and 3-methylbut-2-enoic acid (20.3 g, 203.2 mmol), was added concentrate sulfuric acid (11 mL, 96%, 206.3 mmol) at 0° C. The reaction mixture was stirred at 0° C. for 15 min, then heated to 70° C. and stirred under nitrogen overnight. Upon completion, the reaction was cooled to room temperature, quenched with ice water (500 mL) and extracted with ether (1×). The phases were separated, and the organic layer was washed with 2N NaOH (1×). The combined aqueous layers were acidified to pH 1 with 12N HCl at 0° C. and extracted with ether (1×). The organic layer was washed with brine, dried over Na2SO4, filtered and concentrated under reduced pressure to give the title compound as a red-brown oil (14.4 g, contained <20% 3-methylbut-2-enoic acid) 1H NMR (400 MHz, DMSO-d4) δ 1.33 (s, 6H), 2.53 (s, 2H), 3.31 (s, 3H), 3.79 (s, 3H). 7.08-7.31 (m, 3H), 11.87 (s, 1H).

Provenance & Evidence