反应详情

温度

0 °C

To a dry flask are added 2-hydroxy-4-nitro-benzoic acid methyl ester (40 mmol) (from Example 1h) and triphosgene (26.6 mmol) and DCM (100 mL). The reaction mixture is cooled to 0° C. and diisopropylethylamine (40 mmol) is added slowly. After addition the mixture is warmed to rt. After 1 h at this temperature it is refluxed for 1 h. The mixture is cooled down and the solvents are removed. THF (100 mL), Et3N (80 mmol), and N-methyl piperazine (80 mmol) are added and the mixture is stirred at rt overnight. The solvent is removed and the residue dissolved in EtOAc. Phases are separated upon addition of a 10% solution of NaHCO3. The organic phase is washed with brine, dried on Na2SO4 and evaporated. The crude is used in the following reaction.

1. additionAfter addition the mixture
2. temperatureis warmed to rt
3. temperatureAfter 1 h at this temperature it is refluxed for 1 h
4. temperatureThe mixture is cooled down
5. customthe solvents are removed
6. customThe solvent is removed
7. dissolutionthe residue dissolved in EtOAc
8. customPhases are separated upon addition of a 10% solution of NaHCO3
9. washThe organic phase is washed with brine
10. customdried on Na2SO4
11. customevaporated
12. customThe crude is used in the following reaction