反应 #3204457
相关文献 (1)
openreactiondata ↗doi:10.6084/m9.figshare.5104873.v1; patent:US07405218B2
反应条件: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.
实验步骤: A mixture of 1-bromo-2,5-difluoro-4-methyl-benzene (3.3 g, 16 mmol) and ether (75 mL) was cooled to −78° C., and a solution of n-butyllithium in hexane (5.4 mL, 2.5 M, 13.5 mmol) was added dropwise. After stirring for 1 hour, dimethylformamide (1.1 mL, 14 mmol) was added, and the mixture was stirred for 1 hour. The mixture was treated with 1M HCl and water, warmed to ambient temperature and was extracted 3× with ether. The combined organic layers were dried over MgSO4, filtered and concentrated in vacuo. The residue was diluted with tetrahydrofuran (50 mL), and the mixture was treated with sodium borohydride (0.50 g, 13.5 mmol) and ethanol (2 mL). After stirring for 30 minutes, the mixture was diluted cautiously with 0.5M aqueous HCl, extracted 3× with ethyl acetate, and the combined organic layers were dried over Na2SO4, filtered and concentrated in vacuo. Recrystallization of the residue from hexane afforded 1.24 g (54%) of (2,5-difluoro-4-methyl-phenyl)-methanol as a colorless solid. 1H NMR (400 MHz, CDCl3) δ 7.05 (dd, 1H, J=6.0, 9.2 Hz), 6.84 (dd, 1H, J=6.4, 10 Hz), 4.68 (d, 2H, J=6.0 Hz), 2.23 (s, 3H), 1.76 (t, 1H, J=6.0 Hz) ppm. the mixture was stirred for 1 hour warmed to ambient temperature was extracted 3× with ether The combined organic layers were dried over MgSO4 filtered concentrated in vacuo The residue was diluted with tetrahydrofuran (50 mL) After stirring for 30 minutes extracted 3× with ethyl acetate the combined organic layers were dried over Na2SO4 filtered concentrated in vacuo Recrystallization of the residue from hexane
来源 ID: ord-7745af5b3dcb438996e6cd0486d6699d