[Br:1][C:2]1[S:6][N:5]=[C:4]([C:7]([F:10])([F:9])[F:8])[C:3]=1[C:11](O)=[O:12]>O1CCCC1>[Br:1][C:2]1[S:6][N:5]=[C:4]([C:7]([F:9])([F:10])[F:8])[C:3]=1[CH2:11][OH:12]Into a 50-mL round-bottom flask purged and maintained with an inert atmosphere of nitrogen, was placed 5-bromo-3-(trifluoromethyl)-1,2-thiazole-4-carboxylic acid (800 mg, 2.90 mmol, 1.00 equiv), tetrahydrofuran (3 mL). This was followed by the addition of BH3 (14.5 mL, 5.00 equiv) dropwise with stirring at 0° C. The resulting solution was stirred overnight at 25° C. The reaction progress was monitored by TLC (ethyl acetate/petroleum ether=1:5). The reaction was then quenched by the addition of 20 mL of methanol. The reaction mixture was heated to reflux for 1 h. The residue was applied onto a silica gel column with ethyl acetate/petroleum ether (1:5). This resulted in 200 mg (25%) of [5-bromo-3-(trifluoromethyl)-1,2-thiazol-4-yl]methanol as yellow oil.
Wird geladen…