反应详情

温度

23 °C

To 404 mg (1.53 mmol) of 1,3-dibutyl-3,7-dihydro-purine-2,6-dione in 15 mL of CH2Cl2 at 23° C. was added 0.40 mL (296 mg, 2.29 mmol) i-Pr2NEt followed by 373 mg (1.68 mmol) of 3-nitrobenzenesulfonyl chloride. After stirring at 23° C. for 19 h, the reaction mixture was poured into 50 mL brine and extracted with 3×50 mL of EtOAc. The combined organics were successively washed with 1×50 mL sat. NaHCO3 solution, 1×50 mL H2O, 1×50 mL brine, dried over MgSO4, filtered and evaporated to an oily yellow solid. Flash chromatography on silica gel, eluting with CH2Cl2/EtOAc (40/1), gave a white solid. Recrystallization from hot hexanes/EtOAc gave 540 mg (1.20 mmol, a 79% yield) of the title compound as a white, crystalline solid. mp: 178-179° C.; 1H NMR (300 MHz, CDCl3); δ 0.88-0.98 (m, 6H), 1.22-1.42 (m, 4H), 1.50-1.61 (m, 2H), 1.63-1.75 (m, 2H), 3.92 (t, J=7.5 Hz, 2H), 4.07 (t, J=7.5 Hz, 2H) 7.86 (t, J=8.1 Hz, 1H), 8.34 (s, 1H), 8.55 (d, J=8.1 Hz, 1H), 8.77 (d, J=8.2 Hz, 1H), 9.01 (brt, 1H); IR (KBr, cm−1): 3142w, 2963m, 2935m, 2876w, 1716s, 1661s, 1538s, 1441m, 1396s, 1181s, 1130m, 761m, 670m; MS (ES) m/z (relative intensity): 450 (M++H, 100).

1. extractionextracted with 3×50 mL of EtOAc
2. washThe combined organics were successively washed with 1×50 mL sat. NaHCO3 solution, 1×50 mL H2O, 1×50 mL brine
3. dry with materialdried over MgSO4
4. filtrationfiltered
5. customevaporated to an oily yellow solid
6. washFlash chromatography on silica gel, eluting with CH2Cl2/EtOAc (40/1)
7. customgave a white solid
8. customRecrystallization from hot hexanes/EtOAc
9. customgave 540 mg (1.20 mmol