反应详情

Ex-109C: A solution of 1-(2,4-dimethoxy-benzoyl)amino-3-isobutyl-thiourea (Ex-109B, 0.5 g, 1.61 mmol) and sodium hydroxide (0.999M, 4.8 mL, 4.8 mmol) in ethanol (30 mL) was refluxed for one day. The solvent was removed under reduced pressure and the residue redissolved in ethyl acetate. The solution of ethyl acetate was washed with water and brine, dried over sodium sulfate, and concentrated to give 5-(2,4-dimethoxy-phenyl)-4-isobutyl-4H-[1,2,4]triazole-3-thiol (0.1 g). Additional product (0.36 g, 98% overall) was obtained by extracting the water wash with dichloromethane and a mixture of isopropyl alcohol (33%, v/v, in dichloromethane). 1H NMR (CDCl3) δ 10.82 (bs, 1H), 7.24 (d, J=8.1 Hz, 1H), 6.56 (dd, J=8.1, 2.4 Hz, 1H), 6.51 (d, J=2.4 Hz, 1H), 3.85 (s, 3H), 3.77 (s, 3H), 3.72 (d, J=6.7 Hz, 2H), 2.17–2.08 (m, 1H), 0.70 (d, J=6.7 Hz, 6H).

1. customThe solvent was removed under reduced pressure
2. dissolutionthe residue redissolved in ethyl acetate
3. washThe solution of ethyl acetate was washed with water and brine
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated