反应详情

温度

0 °C

A mixture of intermediate (2-a) (0.023 mol) and triethylamine (0.046 mol) in DCM (40 ml) was stirred at 0° C. A mixture of methanesulfonyl chloride (0.035 mol) in DCM (10 ml) was added dropwise. The mixture was stirred on an ice bath for 2 hours and then washed with H2O/NaCl. The organic layer was dried, filtered and the solvent was evaporated. The residue (oil) was solidified in DIPE. The precipitate was filtered off and dried, yielding 5 g of (S)-2,3-dihydro-1,4-dioxino[2,3-b]pyridine-3-methanol methanesulfonate (ester) (intermediate 3) ([α]D20−27.89°; c=25.10 mg/5 ml in methanol; mp. 136° C.).

1. additionwas added dropwise
2. stirringThe mixture was stirred on an ice bath for 2 hours
3. washwashed with H2O/NaCl
4. customThe organic layer was dried
5. filtrationfiltered
6. customthe solvent was evaporated
7. filtrationThe precipitate was filtered off
8. customdried