Sulfuric Acid → HCID 178423839, compound

Participants

Reaction Conditions

Reaction Steps

Concentrated sulfuric acid (18 M; 7.0 mL) was added to 2,2-dimethoxy-N-(2-methylbenzyl)-acetamide (3.04 g, 13.6 mmol) at ambient temperature, and the solution was stirred overnight at ambient temperature and 6 h at 60° C. The cooled reaction mixture was added to ≈50 mL of ice, and the pH of the yellow mixture was adjusted to 7 with NaHCO3 solution. The yellow precipitate was filtered off, washed with water, and dried in vacuo overnight. The yellow solid thus obtained was triturated from EtOH, the mother liquor was concentrated to give a solid, which was triturated against from EtOH. After four such triturations, the mother liquor was adsorbed onto Hydromatrix and chromatographed on silica gel [20 g/70 mL prepacked cartridge, eluting with DCM→2% MeOH in DCM→3% MeOH in DCM→4% MeOH in DCM]. Fractions containing the title compound were combined and dried in vacuo, giving a yellow oil. It was used in the next step without further purification. 1H NMR (400 MHz, DMSO-d6): δ=10.9 (brs, 1H), 8.96 (s, 1H), 7.51 (d, J=8.0 Hz, 1H), 7.42 (dd, J=6.8, 8.0 Hz, 1H), 7.12-6.97 (m, 2H), 6.85 (s, 1H), 2.64 (s, 3H). MS(ES+): m/z=160.06 (100) [MH+]. HPLC: tR=2.27 min (polar—5 min, ZQ3).

Provenance & Evidence