反应详情

4-Chloro-2-fluoro-5-(1-methylethoxy)phenyl isothiocyanate (2.8 g) was added to a solution of 2-ethoxycarbonyl-3,4,5,6-tetrahydro-(1H, 2H)-pyridazine (1.8 g) and several drops of triethylamine in toluene (5 ml), and the resultant mixture was stirred at 25° C. overnight. Water was added to the mixture, which was then extracted with toluene. The toluene layer was washed with water, dried and concentrated. The residue was purified by silica gel column chromatography to give 2 g of ethyl 2-(4-chloro-2-fluoro-5-(1-methylethoxy)phenylaminothioxomethyl)-3,4,5,6-tetrahydro-1(2H)pyridazine carboxylate. nD27.5 1.5534. NMR δ (ppm): 1.3 (3H, t), 1.4 (6H, d), 1.8 (4H, m), 4.35 (2H, q), 7.1 (1H, d), 8.0 (1H, d), 8.45 (1H, m, ##STR12##

1. extractionwas then extracted with toluene
2. washThe toluene layer was washed with water
3. customdried
4. concentrationconcentrated
5. customThe residue was purified by silica gel column chromatography