3',5'-Difluoroacetophenone → 2-(3,5-Difluorophenyl)propan-2-ol

関与物質

反応手順

To a solution of 1-(3,5-difluorophenyl)ethanone (1.0 equiv) in THF (0.2 M) at 0° C. was added methylmagnesium bromide (1.0 M in THF, 1.15 equiv). After stirring for 4 hours the reaction was quenched by addition of NH4Cl(sat.), diluted with EtOAc, washed with NaCl(sat.), dried over MgSO4, filtered, concentrated and purified by ISCO SiO2 chromatography to yield 2-(3,5-difluorophenyl)propan-2-ol. To a solution of 2-(3,5-difluorophenyl)propan-2-ol in CH2Cl2 (0.1 M) at 0° C. was added 2.6 lutidine (6 equiv.) and than triisopropylsilyl trifluoromethanesulfonate (3.0 equiv.). After stirring for 3 hours at 0° C. and six hours at rt the solution was partitioned between EtOAc and NaHCO3(sat.), separated, washed with NaCl(sat.), dried over MgSO4, filtered, concentrated and purified by ISCO SiO2 chromatography to yield (2-(3,5-difluorophenyl)propan-2-yloxy)triisopropylsilane. (400 MHz, <cdcl3>) δ ppm 1.05-1.08 (m, 21H) 1.57 (s, 6H) 6.63 (s, 1H) 7.00 (dd, J=9.39, 2.35 Hz, 2H).

情報源と証拠