Acetic Acid → HCID 59807081, compound

Participants

Reaction Steps

A solution of compound 4 (0.79 g, 2.68 mmol) in anhydrous methanol (10 mL) was treated with formaldehyde (37% in H2O, 0.26 g, 3.22 mmol) followed by acetic acid (0.38 mL, 6.707 mmol) and NaCNBH3 (0.20 g, 3.22 mmol) at room temperature. The reaction mixture was stirred at room temperature for overnight (16 h). The reaction was basified with 2 N NaOH (50 mL) and the product extracted into CH2Cl2 (2×25 mL). The combined organic layers were washed with brine (25 mL), dried (Na2SO4) and concentrated. The crude product was purified by column chromatography (CH2Cl2, followed by 2 N NH3 in MeOH:CH2Cl2, 5:95) to give compound 5 (0.74 g, 90%) as a brown solid. 1H NMR (DMSO-d6) δ 1.48-1.49 (m, 2H), 1.59-1.72 (m, 3H), 2.22 (s, 3H), 2.54-2.66 (m, 5H), 2.89-2.90 (m, 2H), 3.33 (brs, 2H), 3.90-3.94 (m, 1H), 6.78 (d, 1H, J=8.5 Hz), 7.20 (dd, 1H, J=2.5, 8.5 Hz), 7.26 (d, 1H, J=2.5 Hz); ESI-MS (m/z, %): 311 (MH+, 97), 309 (100).

Provenance & Evidence