反应详情

The crude 2-(furan-2-yl)-2-(methoxyimino)acetic acid (Example 2a) was dissolved in 100 mL of MeOH and was added to a solution of acetyl chloride (3.82 ml, 53.5 mmol) in 50 mL of MeOH. After refluxing for 16 hr, solvent was removed on the rotary evaporator and the crude product was added to 100 mL EtOAc and 20 mL of water. The organic layer was washed with 20 mL of a saturated solution of NaCl, dried (MgSO4) and solvent removed to give methyl 2-(furan-2-yl)-2-(methoxyimino)acetate (6.35 g, 32.9 mmol, 92% yield) as a yellow oil. The product is a 4:1 mixture of isomers by H NMR. Major Isomer: 1H NMR (400 MHz, Chloroform-d) δ 7.53 (dd, J=1.7, 0.6 Hz, 1H). 7.31 (dd, J=3.5, 0.6 Hz, 1H), 6.54 (dd, J=3.5, 1.8 Hz, 1H), 4.15 (s, 3H), 3.94 (s, 3H); 13C NMR (101 MHz, Chloroform-d) δ 162.77, 144.82, 143.80, 142.47, 119.34, 111.78, 63.95, 53.10. HRMS-ESI (m/z) calc'd for [C8H9NO4]+, 183.0532. found, 183.0539.

1. temperatureAfter refluxing for 16 hr
2. customsolvent was removed on the rotary evaporator
3. additionthe crude product was added to 100 mL EtOAc and 20 mL of water
4. washThe organic layer was washed with 20 mL of a saturated solution of NaCl
5. dry with materialdried (MgSO4) and solvent
6. customremoved