反应详情

A solution of 1-bromo-4-(tert-butyl-diphenyl-silanyloxy)-3,3-dimethyl-butan-2-one (40 g, 92.3 mmol) and thiourea (8.4 g, 110.5 mmol) in 400.0 mL of acetonitrile is heated under reflux for 4 h. After cooling the reaction mixture to room temperature, water is added and the aqueous layer is extracted with ethyl acetate; the organic layer is dried over anhydrous Na2SO4, filtered and the solvent is removed under reduced pressure to afford the crude product that is purified by silica gel chromatography to afford 2.3 g of 4-[2-(tert-Butyl-diphenyl-silanyloxy)-1,1-dimethyl-ethyl]-thiazol-2-ylamine as a light brown solid. Yield: 4%, over two steps; 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 1.00 (9H, s), 1.25 (6H, s), 3.62 (2H, s), 5.60 (2H, s), 6.15 (1H, s), 7.25-7.40 (6H, m), 7.50-7.60 (4H, m); m/z 411 [M+H].

1. temperatureunder reflux for 4 h
2. extractionthe aqueous layer is extracted with ethyl acetate
3. dry with materialthe organic layer is dried over anhydrous Na2SO4
4. filtrationfiltered
5. customthe solvent is removed under reduced pressure
6. customto afford the crude product that
7. customis purified by silica gel chromatography