反应详情

To a stirred solution of 646 mg (1.47 mmol) of (R)-(2-tert-butyl-dimethylsilanoxy)-2-pyridin-3-yl-ethyl)-(2-(4-oxazol-4-yl-phenoxy)-ethyl)-amine l-5 in 5 ml of dry tetrahydrofuran at room temperature was added 2.2 ml (2.20 mmol) of 1.0 M tetrabutylammonium fluoride in tetrahydrofuran. The mixture was stirred at room temperature overnight, poured into 100 ml of water, and extracted with ethyl acetate (2×100 ml). The organic extracts were combined, washed successively with water (1×20 ml) and brine (1×20 ml), dried over magnesium sulfate, and concentrated in vacuo to furnish a solid. Chromatography on silica gel eluting with methanol:dichloromethane (1:9, v/v) yielded a solid. Trituration with 10 ml of ethyl acetate:hexanes (1:1, v/v) afforded 250 mg (52% yield) of title compound as a white solid, m.p. 98-100° C., αD=−31.6° (c=0.58, chloroform). Chiral HPLC analysis of the product on 4.6×5 cm Chiralpak AS® column (Chiral Technologies; Exton, Pa.) eluting with acetonitrile:methanol (95:5, v/v) at 1.0 ml/minute revealed an enantiomeric excess of >99.9%.

1. extractionextracted with ethyl acetate (2×100 ml)
2. washwashed successively with water (1×20 ml) and brine (1×20 ml)
3. dry with materialdried over magnesium sulfate
4. concentrationconcentrated in vacuo
5. customto furnish a solid