反应详情

A solution of tetrabutylammonium fluoride (1M in THF) (7.39 mL, 7.39 mmol) was added in one portion to a stirred solution of (S)-2-(tert-butyldimethylsilyloxy)-3-cyclobutoxy-N-(5-methylpyrazin-2-yl)propanamide (Intermediate R2) (2.7 g, 7.39 mmol) in tetrahydrofuran (25 mL) and the resulting solution was stirred at ambient temperature for 4 hours. The reaction mixture was concentrated under vacuum, diluted with ethyl acetate (50 mL) and washed sequentially with water (20 mL) and saturated brine (20 mL). The organic layer was dried (MgSO4) and evaporated. The residue was purified by flash silica chromatography, eluting with ethyl acetate to afford the product (1.5 g, 81%). 1H NMR (400 MHz, CDCl3) δ 1.48-1.56 (1H, m), 1.70-1.76 (1H, m), 1.90-2.00 (2H, m), 2.19-2.26 (2H, m), 2.54 (3H, s), 3.61 (1H, d), 3.67-3.73 (2H, m), 3.97-4.05 (1H, m), 4.35-4.38 (1H, m), 8.14 (1H, d), 9.15 (1H, s), 9.43 (1H, d); m/z (ESI+) (M+H)+=252; HPLC tR=1.31 min.

1. concentrationThe reaction mixture was concentrated under vacuum
2. additiondiluted with ethyl acetate (50 mL)
3. washwashed sequentially with water (20 mL) and saturated brine (20 mL)
4. dry with materialThe organic layer was dried (MgSO4)
5. customevaporated
6. customThe residue was purified by flash silica chromatography
7. washeluting with ethyl acetate