反应详情

Isobutyric anhydride (0.5 mL) is added to a mixture of 131 (45 mg) in methylene chloride (10 mL). The mixture is stirred at room temperature for 1 hour. The solvent is removed to get residue, LC-MS (M+1) 398.17. The residue is dissolved in POCl3 (1 mL), and the mixture is heated at 85° C. for 1 hour. Excess POCl3 is removed. The residue is dissolved in methylene chloride, and washed with sat. NaHCO3, dried, and purified by TLC with 5% MeOH in methylene chloride to give the title product (156). 1H NMR δ (CDCl3) 1.02 (t, 3H, J=5.4 Hz), 1.43 (d, 6H, J=6.0 Hz), 1.71 (p, 2H, J=5.4 Hz), 2.93 (m, 2H), 3.29 (sep, 1H, J=6.0 Hz), 5.57 (s, 2H), 7.22–7.36 (m, 2H), 7.70–7.82 (m, 2H), 8.82 (d, 1H, J=3.3 Hz), 9.04 (s, 1H). LC-MS (M+1) 380.17.

1. customThe solvent is removed
2. customto get residue, LC-MS (M+1) 398.17
3. temperaturethe mixture is heated at 85° C. for 1 hour
4. customExcess POCl3 is removed
5. dissolutionThe residue is dissolved in methylene chloride
6. washwashed with sat. NaHCO3
7. customdried
8. custompurified by TLC with 5% MeOH in methylene chloride