2-(3-bromofuran-2-yl)ethanol

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: n-Butyllithium (2.5M in hexanes, 12.9 mL) was added to a solution of 2,3-dibromofuran (6.63 g) in diethyl ether (40 mL) at −78° C. under nitrogen and the mixture was stirred for 15 minutes. A solution of ethylene oxide (15 mL) in diethyl ether (40 mL) was then added. The reaction mixture was stirred for a further 10 minutes then warmed to room temperature and stirred for 30 minutes. Saturated aqueous ammonium chloride was added and the organic layer was separated, dried (MgSO4) and filtered. The filtrate was evaporated to dryness and the residue was purified by chromatography on silica, eluting with a mixture of ethyl acetate and cyclohexane with a gradient of 5-25% to give 2-(3-bromofuran-2-yl)-ethanol (3.81 g) as a yellow oil. The reaction mixture was stirred for a further 10 minutes stirred for 30 minutes the organic layer was separated dried (MgSO4) filtered The filtrate was evaporated to dryness the residue was purified by chromatography on silica eluting with a mixture of ethyl acetate and cyclohexane with a gradient of 5-25%

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: tert-Butyldimethylsilyl trifluoromethanesulfonate (4.47 g) was added to a solution of 2-(3-bromofuran-2-yl)-ethanol (Intermediate 35, 2.94 g) and pyridine (2.43 g) in DCM (40 mL) and the mixture was stirred for 90 minutes. Water was added and the organic layer was separated, dried (Na2SO4) and filtered. The filtrate was evaporated to dryness and the residue was purified by chromatography on silica, eluting with a mixture of DCM and cyclohexane with a gradient of 0-25% to give [2-(3-bromo-furan-2-yl)-ethoxy]-tert-butyldimethylsilane (3.98 g) as a colourless oil. The material was used without further characterisation. the organic layer was separated dried (Na2SO4) filtered The filtrate was evaporated to dryness the residue was purified by chromatography on silica eluting with a mixture of DCM and cyclohexane with a gradient of 0-25%