Cesium carbonate → Methyl 6-methoxycarbonylmethoxy-2-naphthoate

Beteiligte Stoffe

Reaktionsschritte

To a stirred solution of 6-hydroxy-2-naphthoic acid methyl ester (0.500 g, 2.47 mmol) in acetone (25 mL) at rt was added Cs2CO3 (0.886 g, 2.72 mmol) followed by methyl bromoacetate (0.257 mL, 2.72 mmol) dropwise. After 18 h at this temperature, it was diluted with EtOAc (200 mL). This layer was washed with 1 N HCl (20 mL), sat. aq. NaHCO3 (20 mL), and brine (20 mL) and then dried (MgSO4). After concentration, the residue was recrystallized from MeOH:H2O to afford the product (0.573 g, 85%) as a solid; 1H NMR (DMSO-d6) δ3.71 (s, 3H), 3.87 (s, 3H), 4.95 (s, 2H), 7.30 (dd, J=2.6, 8.9 Hz, 1H), 7.38 (d, J=2.4 Hz, 1H), 7.87 (d, J=8.7 Hz, 1H), 7.92 (dd, J=1.6, 8.6 Hz, 1H), 8.06 (d, J=9.1 Hz, 1H), 8.55 (s, 1H); mass spectrum [(+) ESI], m/z 275 (M+H)+.

Herkunft & Nachweise