反应详情

A stirred solution of 3-bromobenzyl alcohol (21) (10.0 g, 53.5 mmol), 4-dimethylaminopyridine (0.33 g, 2.7 mmol), and t-butylchlorodiphenylsilane (17.6 g, 64.2 mmol) in anhydrous CH2Cl2 (240 mL) was cooled to 0° C. under argon. Triethylamine (8.1 g, 80.2 mmol) was added dropwise via syringe and the reaction mixture was allowed to warm to room temperature over 3.5 h. The reaction solution was washed with water, and the aqueous portion was extracted again with CH2Cl2. The organic layers were combined, washed sequentially with 1N HCI solution, water, and saturated sodium chloride solution, dried over anhydrous magnesium sulfate, filtered, and concentrated to afford 25.3 g of 22 as a clear, pale yellow oil. Purification by column chromatography (20:1 ratio silica gel/crude product; elution with 5% to 7.5% ethyl acetate/hexanes) yielded 21.2 g (93%) of 22 as a pale yellow oil. 1H NMR (300 MHz, CDCl3) δ7.63-7.65 (m, 4H, ArH), 7.35-7.48 (m, 8 H, ArH), 7.18-7.28 (m, 2H, ArH), 4.72 (s, 2H, CH2OSi), and 1.05 (s, 9H, SiC(CH3)3).

1. washThe reaction solution was washed with water
2. extractionthe aqueous portion was extracted again with CH2Cl2
3. washwashed sequentially with 1N HCI solution, water, and saturated sodium chloride solution
4. dry with materialdried over anhydrous magnesium sulfate
5. filtrationfiltered
6. concentrationconcentrated