反应详情

Triethyl phosphonoacetate (5.1 mL, 22.8 mmol) was added to a solution of LDA (22.8 mmol) in THE (100 mL) at −30° C. under an atmosphere of nitrogen. The mixture was stirred at this temperature for 1 h, then a solution of 1-(4-fluorophenyl)-1-formyl-1,3-dihydro-5-isobenzofurancarbonitrile (5.8 g, 21.7 mmol) in THE (50 mL) was added. The mixture was allowed to warm to room temperature during 2.5 h, then poured into ice/H20. The pH was adjusted to about 5 by addition of acetic acid and the aqueous phase was extracted with iEt2O, dried and evaporated. The crude product (8.0 g) was hydrogenated in ethanol (150 mL) using Pt/C (1.7 g, 5%) as catalyst. After 16 h, the mixture was filtered through Celite and evaporated. Silica gel chromatography (heptane, EtOAc 5:1) afforded the product as an oil (4.2g. 57%). 1H NMR (CDCl3) δ 1.20 (3H, t, J=7.0 Hz); 2.25 (2H, m); 2.50 (2H, m); 4.05 (2H, q, J=7.0 Hz); 5.15 (1H, d, J=12.7 Hz); 5.19 (1H, d, J=12.7 Hz); 7.02 (2H, t, J=9.0 Hz); 7.40 (3H, m); 7.50 (1H, s); 7.60 (1 H, d, J=8.0 Hz).

1. additionpoured into ice/H20
2. extractionthe aqueous phase was extracted with iEt2O
3. customdried
4. customevaporated
5. waitAfter 16 h
6. filtrationthe mixture was filtered through Celite
7. customevaporated