Reaction #1596988

Reaction equation

6-Amino-9-benzyl-2-(2-methoxy-ethoxy)-9H-purin-8-ol

DIEA

ethyl chloroformate

ethyl chloroformate

methanol

→

compound 51

Yield 80.0%

Carbonic acid 6-amino-9-benzyl-2-(2-methoxy-ethoxy)-9H-purin-8-yl ester ethyl ester

Yield 80.0%

Solvents

CH2Cl2

dichloromethane

dichloromethane

Conditions

Workup

1. 1
   workup.ADDITIONwere then added to the suspension
2. 2
   Temperatureto warm to room temperature for 15 minutes
3. 3
   TemperatureThe reaction mixture was heated to 35° C.
4. 4
   workup.ADDITIONwere added until the reactions
5. 5
   OtherThe crude mixture was purified by flash chromatography
6. 6
   OtherThe desired peaks were collected
7. 7
   Concentrationconcentrated in-vacuo

Procedure

6-Amino-9-benzyl-2-(2-methoxy-ethoxy)-9H-purin-8-ol, 29 (11.75 mg, 0.027 mmol, prepared according to the procedure described by Kurimota, et al., Bioorg. Med. Chem., 12, 1091-109 (2004) was suspended in CH2Cl2 (0.6 mL) and cooled to 0° C. DIEA (11.96 μL, 0.068 mmol) and ethyl chloroformate (3.86 mg, 0.036 mmol, added as a 10% by volume solution in dichloromethane) were then added to the suspension. The reaction mixture was stirred at 0° C. for 10 minutes then allowed to warm to room temperature for 15 minutes. TLC of the reaction mixture shows that starting material remained. The reaction mixture was heated to 35° C., DMAP (cat.), methanol (60 μL portions) was added to dissolve 29, and additional aliquots of ethyl chloroformate (3.86 mg, 0.036 mmol, added as a 10% by volume solution in dichloromethane) were added until the reactions was complete. The crude mixture was purified by flash chromatography using a 0 to 100% gradient of ethyl acetate in hexane. The desired peaks were collected and concentrated in-vacuo to yield 8.5 mg (80%) of compound 51 as a white solid: 1H NMR (400 MHz, CDCl3) δ 7.45 (d, J=Hz, 2H), 7.27 (m, 3H), 4.98 (s, 2H), 4.46 (m, 4H), 3.74 (m, 2H), 3.42 (s, 2H), 1.46 (t, 3H); MS [M+H]+m/z 388.3.

Source