反应详情

(−)-5′-Amino-3-methyl-spiro[imidazolidine-4,2′-indane]-2,5-dione (265 mg, 1.15 mmol, described in Intermediate 8) was dissolved in AcOH (7 mL) and N-chlorosuccinimide (145 mg, 1.09 mmol) was added in one portion. The mixture was stirred at ambient temperature for 5 h, then the solvent was removed in vacuo. The residue was partitioned between saturated aqueous NaHCO3 (20 mL) and CH2Cl2 (76 mL). The organic layer was dried (Na2SO4), filtered, and concentrated under reduced pressure. The crude product was purified by silica gel chromatography, eluting with a gradient of CH2Cl2:EtOAc—100:0 to 0:100, to give 5′-amino-4′-chloro-3-methyl-spiro[imidazolidine-4,2′-indane]-2,5-dione, which eluted first, and the title compound, which eluted second. MS: m/z 266 (M+1).

1. customthe solvent was removed in vacuo
2. customThe residue was partitioned between saturated aqueous NaHCO3 (20 mL) and CH2Cl2 (76 mL)
3. dry with materialThe organic layer was dried (Na2SO4)
4. filtrationfiltered
5. concentrationconcentrated under reduced pressure
6. customThe crude product was purified by silica gel chromatography
7. washeluting with a gradient of CH2Cl2