反应详情

3-(4-Oxo-3,4-dihydrophthalazin-1-ylmethyl)benzoic acid (A)(7.0 g, 0.25 mol), ethyl isonipecotate (5 ml, 0.32 mol), 2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium hexafluorophospate (HBTU) (12.3 g, 0.32 mol) and N,N,-diisopropylethylamine (10.0 ml, 0.55 mol) were added to dimethylacetamide (40 ml) and stirred for 18 h. Water (100 ml) was added to the reaction mixture and the product was extracted into dichloromethane (4×50 ml). The combined organic layers were washed with water (3×100 ml), dried over MgSO4, filtered and evaporated in vacuo to yield an oil. To a solution of the oil in tetrahydrofuran (100 ml) was added 10% aqueous sodium hydroxide solution (20 ml) and the reaction was stirred for 18 hours. The reaction was concentrated, washed with ethyl acetate (2×30 ml) and acidified with 2M HCl to pH 2. The aqueous layer was extracted with dichloromethane (2×100 ml), then the extracts were dried over MgSO4, filtered and evaporated to yield 1-[3-(4-oxo-3,4-dihydrophthalazin-1-ylmethyl)benzoyl]piperidine-4-carboxylic acid (C) as a yellow solid (7.0 g, 65%), m/z [M+1]+ 392 (96% purity), δH 1.3-1.8 (5H, m), 2.8-3.1 (4H, m), 4.4 (2H, s), 7.2-7.3 (1H, m), 7.3-7.4 (1H, m), 7.7-8.0 (5H, m), 8.2-8.3 (1H, m), 12.6 (1H, s).

1. extractionthe product was extracted into dichloromethane (4×50 ml)
2. washThe combined organic layers were washed with water (3×100 ml)
3. dry with materialdried over MgSO4
4. filtrationfiltered
5. customevaporated in vacuo
6. customto yield an oil
7. stirringthe reaction was stirred for 18 hours
8. concentrationThe reaction was concentrated
9. washwashed with ethyl acetate (2×30 ml)
10. extractionThe aqueous layer was extracted with dichloromethane (2×100 ml)
11. dry with materialthe extracts were dried over MgSO4
12. filtrationfiltered
13. customevaporated