反应详情

Trimethylsilylated 6-chloropurine (prepared from 50 g (0.32 mol) of 6-chloropurine) is stirred with 5 mol % of the palladium(0) catalyst described above and an equivalent amount of epoxycyclopentene in tetrahydrofuran at room temperature for 24 hours. The reaction solution is heated with methanol for 1.5 hours, the precipitate formed is filtered off with suction, the resulting solution is concentrated and the residue is chromatographed over silica gel using methylene chloride/methanol 20/1. 18.9 g (25% of theory) of 6-chloro-9-[(1RS,4SR)-4-hydroxy-cyclopent-2-en-1-yl]purine (Example 1.5.1.) are obtained as yellowish crystals of melting point 118° C. 1H-NMR (270 MHz, d6 -DMSO), δ[ppm]: 8.80 (s, 1H), 8.62 (s, 1H), 6.25 (m, 1H), 6.08 (m, 1H), 5.60 (m, 1H), 5.31 (d, 1H), 4.76 (m, 1H), 2.95 (m, 1H), 1.81 (m, 1H).

1. customat room temperature
2. customfor 24 hours
3. customthe precipitate formed
4. filtrationis filtered off with suction
5. concentrationthe resulting solution is concentrated
6. customthe residue is chromatographed over silica gel