反应详情

To a stirred solution of triphenylphosphine (5.84 g, 22.25 mmol) in THF (20 mL) was added DIAD (4.50 g 22.25 mmol) dropwise at 0° C. and the resulting solution was stirred for 15 min. Intermediate 104C (3.0 g, 8.90 mmol) in THF (20 mL) was added slowly at 0° C. and stirred at room temperature for 45 min. Intermediate tert-butyl 4-(hydroxymethyl)-2,2-dimethyloxazolidine-3-carboxylate (2.470 g, 10.68 mmol) in THF (20 mL) was added at 0° C. and resulting solution was stirred at room temperature overnight. The volatiles were removed under reduced pressure and the crude compound was purified by silica gel chromatography (40 g REDISEP® column, eluting with 10-13% ethyl acetate in hexanes). Fractions containing the product were combined and evaporated to afford Intermediate 351A (3.5 g, 58.5%) as a pale yellow oil. MS(ES): m/z=552 [M+H]+; 1H NMR (300 MHz, DMSO-d6) δ ppm 4.53-4.18 (m, 6H), 3.96-3.82 (m, 2H), 1.50-1.21 (m, 2H).

1. stirringstirred at room temperature for 45 min
2. customresulting solution
3. stirringwas stirred at room temperature overnight
4. customThe volatiles were removed under reduced pressure
5. customthe crude compound was purified by silica gel chromatography (40 g REDISEP® column, eluting with 10-13% ethyl acetate in hexanes)
6. additionFractions containing the product
7. customevaporated