反应详情

A suspension of methyltriphenylphosphonium bromide (24.8 g, 69.4 mmol) in THF (150 mL) at −78° C. under an atmosphere of nitrogen was added 2.5 M of n-butyllithium in hexane (28 mL, 70 mmol) during a period of 12 mins. The reaction was warmed to room temperature to yield a deep red ylide solution. To the ylide solution, cooled in ice, was introduced 2-methoxypyrimidine-5-carbaldehyde (8 g, 65.6 mmol) in THF (50 mL). The reaction was allowed to reach room temperature and stirred for 3 hours. The result suspension was heated to 60° C. over 30 minutes and then heated at 60° C. for 1 hour. After cooling, the reaction mixture was diluted with water (400 mL) and extracted with EtOAc (2×150 mL). The combined organic layers were washed with brine, dried (MgSO4), and concentrated. The residue was purified by silica gel chromatography (EtOAc/hexane 0-30%) to yield title compound.

1. customto yield a deep red ylide solution
2. temperatureTo the ylide solution, cooled in ice
3. customto reach room temperature
4. temperatureThe result suspension was heated to 60° C. over 30 minutes
5. temperatureheated at 60° C. for 1 hour
6. temperatureAfter cooling
7. extractionextracted with EtOAc (2×150 mL)
8. washThe combined organic layers were washed with brine
9. dry with materialdried (MgSO4)
10. concentrationconcentrated
11. customThe residue was purified by silica gel chromatography (EtOAc/hexane 0-30%)