反应详情

To a solution of 5-phenylvalaric acid (0.2 g, 1.1 mmol) in 3 ml CH2Cl2 was added triethylamine (0.15 ml, 1.1 mmol), followed by isobutyl chloroformate (0.15 g, 1.1 mmol) at 0° C. After stirring for 5 minutes, a solution of 3,3-dimethyl-1-perhydropyridazinylpentane-1,2-dione (0.212 g, 1 mmol) in 1 ml CH2Cl2 was added. The reaction was gradually warmed up to room temperature. The crude material was subject to silica gel purification to yield final product as clear oil (0.20 g, 55%). Rf=0.58 (33% EtOAc/hexane). 1H NMR (CDCl3, 400 MHz): δ 0.89 (t, 3H, J=7.5); 1.24 (s, 6H); 1.37 (m, 2H); 1.68 (m, 6H); 1.74 (m, 4H); 2.23 (m, 2H); 2.62 (t, 2H, J=7.60); 2.80 (m, 2H); 4.53 (m, 2H); 7.21 (m, 5H). Anal. Calcd. for C23H24N2O3: C, 71.47; H, 8.87; N, 7.25. Found: C, 71.54; H, 8.80; N, 7.32.

1. customThe crude material was subject to silica gel purification