تفاعل #44331

معادلة التفاعل

Isoamyl nitrite

[(2R,3R,4R,5R)-3-,4-diacetyloxy-5-(2-amino-6-chloropurin-9-yl)oxolan-2-yl]methy 1 acetate

[(2R,3R,4R,5R)-3,4-diacetyloxy-5-(2-amino-6-chloropurin-9-yl)oxolan-2-yl]methyl acetate

I2

CH2I2

Na2S2O3

→

[(2R,3R,4R,5R)-3,4-diacetyloxy-5-(6-chloro-2-iodopurin-9-yl)oxolan-2-yl]methyl acetate

المذيبات

THF

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةThe mixture was heated
2. 2
   درجة الحرارةunder reflux for 45 minutes
3. 3
   أخرىThis step removed the reddish color
4. 4
   استخلاصThe aqueous layer was extracted 3× with chloroform, which
5. 5
   تجفيفdried over MgSO4
6. 6
   تركيزconcentrated under reduced pressure
7. 7
   أخرىThe product was then purified over a silica gel column
8. 8
   أخرىto collect [(2R,3R,4R,5R)-3,4-diacetyloxy-5-(6-chloro-2-iodopurin-9-yl)oxolan-2-yl]methyl acetate (6.4) (80% crystallized from EtOH)

الإجراء التجريبي

Isoamyl nitrite (5 mL, 37 mmol) was added to a mixture of 5.12 g (12 mmol) [(2R,3R,4R,5R)-3-,4-diacetyloxy-5-(2-amino-6-chloropurin-9-yl)oxolan-2-yl]methy 1 acetate (6.3), I2 (3.04 g, 12 mmol), CH2I2 (10 mL, 124 mmol), and CuI (2.4 g, 12.6 mmol) in THF (60 mL). The mixture was heated under reflux for 45 minutes and then allowed to cool to room temperature. To this solution was added 100 ml of saturated Na2S2O3. This step removed the reddish color. The aqueous layer was extracted 3× with chloroform, which was pooled, dried over MgSO4, and concentrated under reduced pressure. The product was then purified over a silica gel column using CHCl3-MeOH (98:2) to collect [(2R,3R,4R,5R)-3,4-diacetyloxy-5-(6-chloro-2-iodopurin-9-yl)oxolan-2-yl]methyl acetate (6.4) (80% crystallized from EtOH). 1H NMR (300 MHz, CDCl3) 8.20 (s, 1H H-8), 6.17 (d, J=5.41 Hz, 1H, H-1), 5.75 (t, J=5.39 Hz, 1H, H-2), 5.56 (t, J=5.40 Hz, 1H, 1H-3), 4.38 (m, 3H, 1H-4,5), 2.14 (s, 1H, Ac), 2.11 (s, 1H, Ac), 2.10 (s, 1H, Ac).

المصدر