反应详情

Toluene (30 mL) in a 3-necked flask was cooled down to −78° C. n-BuLi (1.6 M in hexane, 8.35 mL, 0.13.35 mmol) was slowly added to the toluene. After 10 minutes a solution of the 3-bromo-5-((triisopropylsilyloxy)methyl)pyridine (4.0 g, 11.62 mmol) in toluene (30 mL) was added dropwise. A yellow solid precipitated. The resulting slurry was aged for 15-30 min, then THF (20 mL) was added slowly, keeping the internal temperature at <−50° C. The mixture was aged for 15 min, then acetone (1.7 mL, 23.24 mmol) was added over 2 min. The solids dissolved and a brown homogeneous solution was obtained. The reaction solution was warmed to rt and quenched with saturated aqueous NH4Cl and diluted with EtOAc. The phases were separated and aqueous layer was extracted with EtOAc twice. The organic layers were combined and concentrated to dryness. Purification by flash chromatography (silica gel, hexanes/EtOAc) gave 2-(5-((triisopropylsilyloxy)methyl)pyridin-3-yl)propan-2-ol as a light yellow solid (3.56 g, 96%). 1H NMR (CDCl3): d: 1.250-1.055 (m, 21H), 1.606 (s, 6H), 4.865 (s, 2H), 7.830 (s, 1H), 8.458 (s, 1H), 8.621 (s, 1H).

1. customA yellow solid precipitated
2. additionTHF (20 mL) was added slowly
3. customat <−50° C
4. waitThe mixture was aged for 15 min
5. dissolutionThe solids dissolved
6. customa brown homogeneous solution was obtained
7. customquenched with saturated aqueous NH4Cl
8. additiondiluted with EtOAc
9. customThe phases were separated
10. extractionaqueous layer was extracted with EtOAc twice
11. concentrationconcentrated to dryness
12. customPurification by flash chromatography (silica gel, hexanes/EtOAc)