Potassium Carbonate → HCID 389495, compound

Participants

Reaction Steps

To a suspension of 205 mg (0.61 mmol) of 15b in 10 mL of dry methanol was added 88 mg of K2CO3. The reaction was stirred at room temperature for 20 min and then concentrated in vacuo. The black residue was flash chromatographed on silica gel using a chloroform/methanol (98:2) mixture as the eluant. The yellow-colored product was recrystallized by dissolving it in a minimum amount of (4:1) chloroform/methanol, adding hexane, and then chilling: 141 mg (78%) yield: dec pt 259° C.; TLC (chloroform:methanol[20:80]) Rf =0.35, IR(KBr pellet) 3237, 3181, 3065, 1741, 1700, 1667, 1632, 1574, 1532, 1404 cm-1 ; 1H NMR (dimethyl sulfoxide-d6) δ9.67 (1 H, s, amide proton), 7.66 (1 H, s, C(8) proton), 5.97 (1 H, d, J= 5.3 Hz, hydroxyl proton), 5.09 (1 H, m, C(3) proton), 4.22 and 4.05 (2 H, 2×m, C(1) diastereomeric methylene), 2.90 and 2.37 (2 H, 2×m, C(2) diastereomeric methylene), 2.27 (3 H, s, 7-methyl proton), 1.97 (3 H, s, acetamido methyl); mass spectrum (EI mode) m/z, 290(P+), 272(P+ -H2O), 248 (P+ -ketene) 244 (P+ -NO2) Anal. Calcd for C13H14N4O4.0.75H2O: C, 51.39; H, 5.13; N, 18.44. Found: C, 51.75; H, 4.77; N, 18.45.

Provenance & Evidence