反应详情

温度

0 °C

To methyl 3-[5-(dimethylcarbamoyl)pyrazin-2-yl]oxy-5-hydroxy-benzoate (10 g, 32 mmol) was added triphenylphosphine (10.3 g, 39.4 mmol), THF (100 mL) and (2R)-1-[(2-methylpropan-2-yl)oxy]propan-2-ol (CAS no. 136656-73-0) (5.21 g, 39.4 mmol). The resulting slurry was cooled to 0° C. and diethylazodicarboxylate (50% w/v in toluene, 13.7 mL, 39.4 mmol) was charged dropwise keeping the temperature below 10° C. After 2 hours the solvent was evaporated under reduced pressure and taken up with ethyl acetate (23 mL). A solid crashed out which was filtered and the mother liquors were evaporated under reduced pressure, taken up into ethyl acetate (23 mL) and isohexane (53 mL) and the resulting solid filtered, the mother liquors were evaporated under reduced pressure and the resulting residue was purified by flash chromatography eluting with 80% ethyl acetate/20% isohexane to afford the product (13.5 g).

1. customthe temperature below 10° C
2. customAfter 2 hours the solvent was evaporated under reduced pressure
3. filtrationwas filtered
4. customthe mother liquors were evaporated under reduced pressure
5. filtrationthe resulting solid filtered
6. customthe mother liquors were evaporated under reduced pressure
7. customthe resulting residue was purified by flash chromatography
8. washeluting with 80% ethyl acetate/20% isohexane