反应详情

温度

20 °C

5 g (0.03 mol) of benzofuran-2,3-dione2-oxime (XI-1) are dissolved in 30 ml of methanol, and at 20° C. 15 ml of a 2 molar solution of sodium methoxide in methanol are added dropwise. The solvent is distilled off under reduced pressure. The crystalline residue is dissolved in 30 ml of N-methyl-2-pyrrolidinone and treated with 6.27 g (0.03 mol) of 2-(2-bromoethoxy)-tetrahydropyran at 20° C. The reaction mixture is stirred for 16 hours at 20° C., poured into 100 ml of water and the resulting mixture is extracted twice with 100 ml of dichloromethane each time. The solvent is distilled off under reduced pressure and the residue is chromatographed over silica gel using a mixture of diethyl ether/dichloromethane/petroleum ether (1:1:2). 5.55 g (62.1% of theory) of benzofuran-2,3-dione2-{O-[2-(tetrahydropyran-2-yloxy)-ethyl]-oxime} (XIV-2) are obtained.

1. customat 20° C
2. distillationThe solvent is distilled off under reduced pressure
3. dissolutionThe crystalline residue is dissolved in 30 ml of N-methyl-2-pyrrolidinone
4. extractionthe resulting mixture is extracted twice with 100 ml of dichloromethane each time
5. distillationThe solvent is distilled off under reduced pressure
6. customthe residue is chromatographed over silica gel using
7. additiona mixture of diethyl ether/dichloromethane/petroleum ether (1:1:2)