反应详情

A solution of allyl-prop-2-ynyl-carbamic acid tert-butyl ester (prepared according to the method of Boger et al., J. Am. Chem. Soc., 1996, 118, 2109; 1.95 g, 10 mmol) in anhydrous tetrahydrofuran (10 mL) was stirred at 0° C. and treated with n-butyllithium (1.6 M solution in hexane; 7.2 mL, 11.5 mmol) during a 5 min period. After being stirred for an additional 5 min, the solution was treated sequentially with hexamethylphosphoramide (2 mL) and a solution of 1-iodopropane (1.71 mL, 17.5 mmol) in tetrahydrofuran (2 mL). After 65 min, the cooling bath was removed and the mixture was allowed to warm to room temperature where it stirred for 80 min. At the conclusion of this period, saturated aqueous ammonium chloride was added, followed by water to dissolve the solids. The mixture was extracted with ethyl acetate, and the combined organic phases were washed with saturated aqueous sodium chloride, dried over sodium sulfate and concentrated to yield a residue. The residue was purified by flash chromatography to provide a pale yellowish oil (1.67 g, 70%). 1H NMR (400 MHz, CDCl3) δ 5.80 (m, 1H), 5.17 (m, 2H), 4.1-3.9 (m, 4H), 2.17 (m, 2H), 1.60 (m, 2H), 1.48 (s, 9H), 0.99 (m, 3H). MS (ES+) m/z 238.27 (M+H+)

1. waitAfter 65 min
2. customthe cooling bath was removed
3. stirringstirred for 80 min
4. additionAt the conclusion of this period, saturated aqueous ammonium chloride was added
5. dissolutionto dissolve the solids
6. extractionThe mixture was extracted with ethyl acetate
7. washthe combined organic phases were washed with saturated aqueous sodium chloride
8. dry with materialdried over sodium sulfate
9. concentrationconcentrated
10. customto yield a residue
11. customThe residue was purified by flash chromatography