تفاعل #88613

معادلة التفاعل

benzyl chloroformate

Sodium hydride

3-bromo-9H-dipyrido[2,3-b;4′,3′-d]pyrrol-5-ol

→

title compound

المردود 17.0%

3-Bromo-5-hydroxy-dipyrido[2,3-b;4′,3′-d]pyrrole-9-carboxylic acid benzyl ester

المردود 17.0%

المذيبات

DMF

DMF

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةa cooled
2. 2
   workup.ADDITIONOn complete addition the mixture
3. 3
   workup.STIRRINGstirred for 15 minutes
4. 4
   workup.STIRRINGstirring
5. 5
   workup.WAITcontinued for 18 hours
6. 6
   أخرىThe solvent was evaporated
7. 7
   workup.ADDITIONthe resultant residue diluted with water
8. 8
   استخلاصextracted with dichloromethane (5×50 mL) and ethyl acetate (3×30 mL)
9. 9
   تجفيفThe combined organic layer was dried over (Na2SO4)
10. 10
    ترشيحfiltered
11. 11
    أخرىevaporated
12. 12
    أخرىto afford a residue
13. 13
    أخرىThe resultant residue was purified by flash chromatography (silica, 12 g cartridge, ISCO, 0-7% methanol in dichloromethane)
14. 14
    أخرىThe appropriate fractions were collected
15. 15
    أخرىevaporated

الإجراء التجريبي

Sodium hydride (167 mg, 4.17 mmol) was added to a cooled (0° C.) mixture of 3-bromo-9H-dipyrido[2,3-b;4′,3′-d]pyrrol-5-ol (1.0 g, 3.79 mmol) in DMF (15 mL). On complete addition the mixture was stirred for 15 minutes then allowed to warm to ambient temperature and stirred for 15 minutes. A solution of benzyl chloroformate (610 mg, 3.6 mmol) in DMF (1 mL) was added and stirring continued for 18 hours. The solvent was evaporated and the resultant residue diluted with water and extracted with dichloromethane (5×50 mL) and ethyl acetate (3×30 mL). The combined organic layer was dried over (Na2SO4), filtered and evaporated to afford a residue. The resultant residue was purified by flash chromatography (silica, 12 g cartridge, ISCO, 0-7% methanol in dichloromethane). The appropriate fractions were collected and evaporated to afford the title compound as a light yellow solid (240 mg, 17%). LCMS (Method B): RT=4.54 min, M+H+=398/400. 1H NMR (400 MHz, DMSO-d6): 8.99 (s, 1H), 8.79 (d, J=2.4 Hz, 1H), 8.63 (d, J=2.4 Hz, 1H), 8.23 (s, 1H), 7.63 (d, J=7.5 Hz, 2H), 7.48-7.36 (m, 3H), 5.61 (s, 2H).

المصدر