Trifluoroacetic acid → HCID 66699272, compound

Participants

Reaction Conditions

Reaction Steps

Ethyl 2-chloro-2-(hydroxyimino)acetate (116 mg, 0.768 mmol) was added to a stirred solution of 3a (0.256 mmol) and triethylamine (357 μL, 2.56 mmol) in THF (10.0 mL) at rt. After approximately 1 h, the reaction mixture was acidified to ˜pH 1 by the addition of TFA, and the resulting mixture was heated to 50° C. for approximately 4.5 h. The reaction mixture was cooled to rt, neutralized with saturated aqueous sodium bicarbonate and concentrated in vacuo. The crude residue was purified by flash chromatography on silica gel (gradient elution; 0%-100% EtOAc/hexanes as eluent) to afford the title compound 3b. m/z (ES) 472 (MH)+. 1HNMR (500 MHz, CDCl3): δ 9.05 (d, 1H, J=2.3 Hz), 8.46 (d, 1H, J=2.4 Hz), 8.29 (d, 1H, J=2.5 Hz), 8.00 (dd, 1H, J=2.3, 8.5 Hz), 7.51 (m, 4H), 7.41 (d, 1H, J=8.2 Hz), 7.36 (m, 1H), 6.98 (s, 1H), 4.50 (q, 2H, J=7.1 Hz), 3.92 (s, 3H), 3.71 (m, 1H), 1.78 (s, 1H), 1.47 (t, 3H, J=7.1 Hz), 0.91 (d, 3H, J=6.7 Hz), 0.88 (d, 3H, J=6.9 Hz).

Provenance & Evidence