反应详情

温度

-50 °C

n-BuLi (2.5 M solution in hexanes, 1.29 g, 8 mL, 20.24 mmol) was added to a stirring, −40° C. solution of tert-butyl(pentadec-14-ynyloxy)diphenylsilane (8.5 g, 18.40 mmol) in THF (175 mL) under an argon atmosphere. After 30 min, the reaction mixture was gradually warmed over 3 h to −10° C., held at this temperature for 20 min, then re-cooled to −50° C. Then, a solution of paraformaldehyde (3.05 g, 92.2 mmol) in THF (30 mL) was cannulated into the stirring reaction mixture. After 30 min, the temperature was gradually warmed over 3 h to room temperature. Following 1 h at room temperature, the reaction mixture was quenched with sat. aq. NH4Cl (10 mL), diluted with ether (100 mL), and washed with water (2×75 mL). The combined aqueous washes were back-extracted with ether (2×50 mL). The combined All of the organic extracts were combined, dried over Na2SO4, and concentrated under reduced pressure. The residue was purified by SiO2 column chromatography using 5% EtOAc/hexanes as eluent to give 16-(tert-butyldiphenylsilyloxy)hexadec-2-yn-1-ol (6.12 g, 68%). TLC: 30% EtOAc/hexanes, Rf≈0.5; 1H NMR (CDCl3, 300 MHz) δ 7.70-7.74 (m, 4H), 7.34-7.44 (m, 6H), 4.3 (t, 2H, J=2.1 Hz), 3.65 (t, 2H, J=7.3 Hz), 2.12-2.17 (m, 2H), 1.20-1.61 (m, 22H), 1.04 (s, 9H).

1. temperaturethe reaction mixture was gradually warmed over 3 h to −10° C.
2. waitheld at this temperature for 20 min
3. waitAfter 30 min
4. temperaturethe temperature was gradually warmed over 3 h to room temperature
5. waitFollowing 1 h at room temperature
6. customthe reaction mixture was quenched with sat. aq. NH4Cl (10 mL)
7. additiondiluted with ether (100 mL)
8. washwashed with water (2×75 mL)
9. extractionThe combined aqueous washes were back-extracted with ether (2×50 mL)
10. dry with materialdried over Na2SO4
11. concentrationconcentrated under reduced pressure
12. customThe residue was purified by SiO2 column chromatography