反应详情

To a solution of 51 mg (0.21 mmol) of 2-(9H-xanthen-9yl)acetic acid in 2 ml of dichloromethane were added 0.1 ml (1.1 mmol) of oxalyl chloride and one drop of N,N-dimethylformamide with ice-cooling, and the resulting mixture was stirred for 3 hours and freed from the solvent and an excess of the reagent by distillation under reduced pressure. The residue was again dissolved in 2 ml of dichloromethane, and 93 mg (0.53 mmol) of 2,6-bis(1-methylethyl)aniline and 0.2 ml of pyridine were added thereto with ice-cooling, followed by stirring at room temperature for 5 hours. After distilling off the solvent, the residue thus obtained was purified by column chromatography through 15 g of silica gel using a 30:0-1 mixture of dichloromethane and ethyl acetate as an eluent to give 78 mg (92%) of the desired compound as crystals.

1. temperaturecooling
2. distillationan excess of the reagent by distillation under reduced pressure
3. dissolutionThe residue was again dissolved in 2 ml of dichloromethane
4. temperaturewith ice-cooling
5. stirringby stirring at room temperature for 5 hours
6. distillationAfter distilling off the solvent
7. customthe residue thus obtained
8. customwas purified by column chromatography through 15 g of silica gel using
9. additiona 30:0-1 mixture of dichloromethane and ethyl acetate as an eluent