反应详情

2-Oxopiperazine (1.5 g, 14.98 mmol, commercially available from e.g. Sigma-Aldrich) was suspended in dry dichloromethane (DCM) (40 mL), cooled in an ice bath before adding triethylamine (3.13 mL, 22.47 mmol), followed by 3-chloro-2-methylbenzoyl chloride (I130) (2.97 g, 15.73 mmol) in Dichloromethane (DCM) (15 mL) dropwise over 15 mins. The reaction mixture was then stirred for 16 hours at RT, under argon. Solvent removed under reduced pressure. Residue partitioned between DCM (100 ml) and water (60 ml). Layers separated and aqueous layer extracted with DCM (2×50 ml). Combined extracts were washed with saturated sodium bicarbonate solution (70 ml), brine (70 ml), dried (Na2SO4), filtered and evaporated to afford an off-white solid. Solid was stirred in n-hexane (50 mL) at 55° C. for 30 mins, before filtering and drying in the vacuum oven at 40° C. for 18 hours to afford the desired product in 3.39 g as a pale yellow solid.

1. temperaturecooled in an ice bath
2. customSolvent removed under reduced pressure
3. customResidue partitioned between DCM (100 ml) and water (60 ml)
4. customLayers separated
5. extractionaqueous layer extracted with DCM (2×50 ml)
6. washCombined extracts were washed with saturated sodium bicarbonate solution (70 ml), brine (70 ml)
7. dry with materialdried (Na2SO4)
8. filtrationfiltered
9. customevaporated
10. customto afford an off-white solid
11. filtrationbefore filtering
12. customdrying in the vacuum oven at 40° C. for 18 hours