Formic Acid → Formamide, N-(2-methylphenyl)-

Participants

Reaction Steps

A mixture of formic acid (14.361 g, 0.312 mol) and acetic anhydride (12.659 g, 0.124 mol) was stirred at room temperature for 1 h under an argon atmosphere. This mixture was added to a solution of 2-methylaniline (10.710 g, 0.1 mol) in dry dichloromethane (60 ml) at such a rate that the temperature of the reaction mixture was kept between 5 and 10° C. The reaction was stirred at room temperature for 16 h and then refluxed for 4 h. The solvent was evaporated under reduced pressure, the residue was dissolved in CHCl3 (200 mL) and washed with a saturated aqueous NaHCO3 solution (3×200 mL), and water (200 mL). The organic layer was dried over Na2SO4 and the solvent was evaporated under reduced pressure. The remaining yellow solid was washed with a mixture of hexanes/diethyl ether (2×10 mL) and then with hexanes (3×5 mL) to afford N-formyl-2-methylaniline 8b as a white solid (9.70 g, 72%). 1H NMR (CDCl3, 300 MHz): δ=9.03-8.18 (m, 2H, CHO, NH), 7.77-7.03 (m, 4H), 2.30-2.22 (m, 3H); 13C{1H}NMR (CDCl3, 75 MHz): δ=164.41, 160.32, 135.50, 134.99, 131.45, 130.82, 130.50, 129.87, 127.25, 126.80, 126.34, 125.84, 123.75, 121.32, 18.05, 17.99; HRMS (FAB+) calculated for C8H10NO [M]+ 136.0762, observed 136.0783.

Provenance & Evidence