反应详情

n-Butyl lithium (a 2.5 m solution in hexane; 28.8 ml, 72 mmol) was added to a solution of morpholine (6.28 ml, 72 mmol) in tetrahydrofuran (700 ml) at -78° under argon. After 20 min., 3-furaldehyde (7.0 g, 72 mmol) was added. After another 20 min., sec-butyl lithium (a 1.3 m solution in cyclohexane; 55.4 ml, 72 mmol) was added dropwise and stirring continued at -780 for 7h before chlorotrimethylsilane (27 ml, 216 mmol) was added. Stirring continued overnight (14h) while the cooling bath was allowed to attain room temperature. The solution was poured into ice cold 10% (v/v) hydrochloric acid (200 ml) and after stirring at 0° for 10 min., the layers were separated. The aqueous phase was extracted with diethyl ether. All the organic phases were combined, dried (magnesium sulfate) and evaporated down to give a light brown oil, which was purified by flash chromatography on silica using 2% ethyl ether/hexane. Fractions with Rf of about 0.30 (silica, 10% ethyl ether/hexane) on evaporation gave 8.22 g (68%) of the title aldehyde as a light yellow oil, bp 48°-50°/0.25 torr.

1. waitAfter another 20 min.
2. addition55.4 ml, 72 mmol) was added dropwise
3. additionwas added
4. customto attain room temperature
5. stirringafter stirring at 0° for 10 min.
6. customthe layers were separated
7. extractionThe aqueous phase was extracted with diethyl ether
8. dry with materialdried (magnesium sulfate)
9. customevaporated down
10. customto give a light brown oil, which
11. customwas purified by flash chromatography on silica using 2% ethyl ether/hexane
12. customFractions with Rf of about 0.30 (silica, 10% ethyl ether/hexane) on evaporation