Phosphorus oxychloride → 4-Chloro-5-phenylthieno[2,3-d]pyrimidine

5-Phenyl-3H-thieno[2,3-d]pyrimidin-4-one (294.6 g, 1.29 mol) was added in portions to stirred phosphoryl chloride (1000 ml), then the stirred suspension was warmed gently to reflux temperature, heated under reflux for 4 hours, and allowed to stand at ambient temperature for 18 hours. The resulting dark solution was removed by decantation from a solid residue and concentrated in vacuo to give a gummy solid. The two solids were combined and added to crushed ice (1000 ml). The product was extracted into dichloromethane (3×500 ml), then the combined extracts were washed with water (2×300 ml) and saturated aqueous sodium hydrogen carbonate solution (500 ml) and dried and decolourised (MgSO4+charcoal). The solvent was removed in vacuo to give 4-Chloro-5-phenyl-thieno[2,3-d]pyrimidine as a yellow/orange solid which was used without further purification.

1. temperaturethe stirred suspension was warmed gently
2. temperatureto reflux temperature
3. temperatureheated
4. temperatureunder reflux for 4 hours
5. customThe resulting dark solution was removed by decantation from a solid residue
6. concentrationconcentrated in vacuo
7. customto give a gummy solid
8. additionadded
9. extractionThe product was extracted into dichloromethane (3×500 ml)
10. washthe combined extracts were washed with water (2×300 ml) and saturated aqueous sodium hydrogen carbonate solution (500 ml)
11. customdried
12. customThe solvent was removed in vacuo

ORD record

ord-5977702b7d954979b90f9837a5c70c78

Source dataset

uspto-grants-2011_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08022076B2