反应详情

温度

0 °C

To a suspension of 1.08 g (4.43 mmol) of 6-acetoxymethyl-2-naphthoic acid in 150 mL of Et2O at 0° C. was added a cold solution of CH2N2 in Et2O which was prepared from 2.0 g (19 mmol) of N-methyl-N-nitrosourea and 30 mL of 40% aqueous KOH. The mixture was stirred at 0° C. for 10 min when all the solid went into solution. Excess CH2N2 was decomposed with HOAc. The reaction mixture was dried over Na2SO4 and concentrated to give 1.6 g of a white solid, which was purified on 100 g of silica gel (50% EtOAc/hexane) to give 1.04 g (91% yield) of the pure methyl ester. A portion was recrystallized from EtOAc/hexane to give white plates: mp 115°-116° C.; IR (mull) 1720, 1300, 1260, 1200, 1140, 1100, 1040, 980, 940, 900, 840, 820, 760 cm-1 ; 1 H NMR (CDCl3) δ2.15 (s, 3, CH3CO2), 3.98 (s, 3, CO2CH3), 5.28 (s, 2, CH2O), 7.3-8.7 (m, 6, ArH); MS calcd for C15H14O4 258.0892, found 258.0872.

1. dry with materialThe reaction mixture was dried over Na2SO4
2. concentrationconcentrated