反应详情

温度

25 °C

To a 2 L stainless steel Parr bomb was added guanosine hydrate (100 g, 0.35 mol, Aldrich), hexamethyl) disilazane (320 mL, 1.52 mol, 4.4 eq.), trimethyl) silyl triflouromethanesulfonate (8.2 mL), and toluene (350 mL). The bomb was sealed and partially submerged in an oil bath (170° C.; internal T 150° C., 150 psi) for 5 days. The bomb was cooled in a dry ice/acetone bath and opened. The contents were transferred with methanol (300 mL) to a flask and the solvent was evaporated under reduced pressure. Aqueous methanol (50%, 1.2 L) was added. The resulting brown suspension was heated to reflux for 5 h. The suspension was concentrated under reduced pressure to one half volume in order to remove most of the methanol. Water (600 mL) was added and the solution was heated to reflux, treated with charcoal (5 g) and hot filtered through Celite. The solution was allowed to cool to 25° C. The resulting precipitate was collected, washed with water (200 mL) and dried at 90° C./0.2 mmHg for 5 h to give a constant weight of 87.4 g (89%) of tan, crystalline solid; mp 247° C. (shrinks), 255° C. (dec, lit. (1) mp 250-252° C.); TLC homogenous (Rf 0.50, isopropanol-ammonium hydroxide-water 16:3:1 ); PMR (DMSO), δ 5.73 (d, 2, 2-NH2), 5.78 (s, 1, H-1), 6.83 (br s, 2, 6-NH2).

1. customThe bomb was sealed
2. custompartially submerged in an oil bath
3. temperatureThe bomb was cooled in a dry ice/acetone bath
4. customthe solvent was evaporated under reduced pressure
5. additionAqueous methanol (50%, 1.2 L) was added
6. temperatureThe resulting brown suspension was heated
7. temperatureto reflux for 5 h
8. concentrationThe suspension was concentrated under reduced pressure to one half volume in order
9. customto remove most of the methanol
10. additionWater (600 mL) was added
11. temperaturethe solution was heated
12. temperatureto reflux
13. additiontreated with charcoal (5 g)
14. filtrationhot filtered through Celite
15. customThe resulting precipitate was collected
16. washwashed with water (200 mL)
17. customdried at 90° C./0.2 mmHg for 5 h
18. customto give a constant weight of 87.4 g (89%) of tan, crystalline solid