반응 #83995
ord-5817d2c8e8db465e9c1b92bbfc342f50
반응 조건
후처리
- 1온도after cooling to 25°
- 2온도The dark purple reaction mixture was heated in a 50° bath under nitrogen for 20 minutes
- 3온도immediately cooled in an ice-water bath
- 4여과the resulting precipitate was collected by filtration
- 5세척washed with cold methanol (2×10 mL)
- 6기타Vacuum-drying overnight
실험 절차
Dideoxyuridine (2.122 g, 10.0 mmol) was dissolved in 30 mL of warm methanol and, after cooling to 25°, iodine monochloride (4.06 g, 25 mmol, 2.5 eq. Fisher) in methanol (20 mL) was added over 5 minutes. The dark purple reaction mixture was heated in a 50° bath under nitrogen for 20 minutes and then immediately cooled in an ice-water bath. After standing without stirring for 165 minutes, the resulting precipitate was collected by filtration and washed with cold methanol (2×10 mL). Vacuum-drying overnight afforded 2.232 g (66%) of iodide 21 as off-white microcrystals. This material was used without further purification in the next reaction, but other preparations were purified by chromatography or recrystallization from boiling methanol (30 mL/g) to give white needles (mp d 160°-164°). NMR indicated that the crude precipitate was homogeneous, but also that the 5'-hydroxy proton was very broad due to exchange catalyzed by trace impurities. Chromatographed or recrystallized materials afforded spectra in which this proton was, as usual, a sharp triplet.