反应详情

Under argon, 52.5 g (0.20 mol) of triphenylphosphine are initially charged in 600 ml of dioxane, and 35.6 g (0.20 mol) of N-bromosuccinimide are added a little at a time, with cooling. The mixture is stirred at RT for 30 min. 8.6 g (0.04 mol) of ethyl [(4-hydroxy-2-pyrimidinyl)thio]acetate are then added and the mixture is heated at reflux for 45 min. A total of 2 l of water are added to the mixture, which is then extracted 3× with in each case 300 ml of methyl tert-butyl ketone. The organic phase is washed 2× with water and 1× with concentrated NaCl solution, dried over magnesium sulphate and concentrated. The residue is stirred in 60 ml of methyl tert-butyl ketone and filtered off. The mother liquor is concentrated and the residue is purified by silica gel chromatography (dichloromethane).

1. temperaturewith cooling
2. temperaturethe mixture is heated
3. temperatureat reflux for 45 min
4. extractionis then extracted 3× with in each case 300 ml of methyl tert-butyl ketone
5. washThe organic phase is washed 2× with water and 1× with concentrated NaCl solution
6. dry with materialdried over magnesium sulphate
7. concentrationconcentrated
8. stirringThe residue is stirred in 60 ml of methyl tert-butyl ketone
9. filtrationfiltered off
10. concentrationThe mother liquor is concentrated
11. customthe residue is purified by silica gel chromatography (dichloromethane)