反应详情

温度

45 °C

To a solution of 4-amino-3-hydroxy-benzoic acid methyl ester (2.0 g) in MeOH (100 mL) was added 2,6-dichlorobenzaldehyde (2.1 g). The reaction mixture was heated at 45° C. overnight, and then concentrated in vacuo. The residue was dissolved in THF (10 mL) and dichloromethane (90 mL). To the mixture solution was added 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (2.72 g). The reaction mixture was stirred for 1 h, diluted with NaHCO3 aqueous solution, extracted with EtOAc, and washed with brine. The extracts were dried over Na2SO4 and concentrated in vacuo. Purification by column chromatography (SiO2, 2:3 EtOAc/Hexane) gave 2-(2,6-dichlorophenyl)-benzooxazole-6-carboxylic acid methyl ester: MS (m/z) 321.9 (M+1).

1. concentrationconcentrated in vacuo
2. dissolutionThe residue was dissolved in THF (10 mL)
3. additionTo the mixture solution was added 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (2.72 g)
4. additiondiluted with NaHCO3 aqueous solution
5. extractionextracted with EtOAc
6. washwashed with brine
7. dry with materialThe extracts were dried over Na2SO4
8. concentrationconcentrated in vacuo
9. customPurification by column chromatography (SiO2, 2:3 EtOAc/Hexane)