反应详情

3-Amino-4-n-propylpyridine-2-carboxylic acid (Preparation 4; 0.36 g, 0.002 mol) was added to a stirred mixture of cesium carbonate (0.325 g, 0.001 mol) in water (20 ml), then this mixture was evaporated under vacuum and the residue azeotroped with dimethylformamide (2×20 ml). The resulting cesium salt was suspended in dimethylformamide (3 ml) and the stirred suspension then treated dropwise with ethyl iodide (0.17 ml, 0.0021 mol). After a further 0.25 hour, the solvent was evaporated under vacuum and the residue partitioned between water (20 ml) and ethyl acetate (20 ml). The organic phase was washed with water (10 ml), dried (MgSO4) and evaporated under vacuum, then the residue crystallized from acetone:hexane to give the title compound as an off-white solid (0.35 g, 84%), m.p. 93-96° C.

1. customthis mixture was evaporated under vacuum
2. customthe residue azeotroped with dimethylformamide (2×20 ml)
3. customthe solvent was evaporated under vacuum
4. customthe residue partitioned between water (20 ml) and ethyl acetate (20 ml)
5. washThe organic phase was washed with water (10 ml)
6. dry with materialdried (MgSO4)
7. customevaporated under vacuum
8. customthe residue crystallized from acetone