tert-butyl-[(4-fluorofuran-2-yl)methoxy]-dimethylsilane

反应条件: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: tert-Butyl-(4-fluorofuran-2-ylmethoxy)dimethylsilane (prepared according to Heffernan et al, US2008 0058395, 6.75 g) was dissolved in anhydrous THF (100 mL), under an atmosphere of nitrogen and cooled to −78° C. n-Butyllithium (2.5M in hexanes, 11.74 mL) was added and the mixture was stirred at −78° C. for 10 minutes. Chlorotrimethylsilane (3.19 g) was added and the mixture was stirred at −78° C. for 40 minutes. Further n-butyllithium (2.5M in hexanes, 11.74 mL) was added and the mixture was stirred at −78° C. for 40 minutes, before triisopropyl borate (11.04 g) was added. The resultant mixture was stirred at −78° C. for 5 minutes then allowed to warm to room temperature. 1M aqueous hydrochloric acid (100 mL) and diethyl ether (50 mL) were added and the mixture was stirred vigorously for 5 minutes. The layers were separated and the organic layer was dried (MgSO4) and filtered. The filtrate was concentrated in vacuo and the residue was purified by chromatography on silica, eluting with a mixture of ethyl acetate and cyclohexane, with a gradient of 0-20% to give 2-(tert-butyldimethylsilanyloxymethyl)-4-fluoro-5-trimethylsilanylfuran-3-yl-boronic acid (6.01 g) as a brown oil which was used without further characterisation. was added the mixture was stirred at −78° C. for 40 minutes was added to warm to room temperature the mixture was stirred vigorously for 5 minutes The layers were separated the organic layer was dried (MgSO4) filtered The filtrate was concentrated in vacuo the residue was purified by chromatography on silica eluting with a mixture of ethyl acetate and cyclohexane, with a gradient of 0-20%

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: tert-Butyl((4,4-difluoro-4,5-dihydrofuran-2-yl)methoxy)dimethylsilane was diluted with DCM and treated with silica gel (5 g SiO2/1 g of compound). The flask was swirled around to ensure an even mix, DCM was allowed to air dry and the flask left at rt overnight. The silica gel was transferred to a fritted funnel and eluted with DCM until no more product could be detected by TLC. The filtrate was concentrated to provide an orange oil tert-butyl((4-fluorofuran-2-yl)methoxy)dimethylsilane. 1H NMR (400 MHz, CDCl3) δ 0.09 (s, 6H), 0.91 (s, 9H), 4.55 (br s, 2H), 6.20 (m, 1H), 7.31 (dd, J=5.03, 0.63 Hz, 1H); 19F NMR (376.19 MHz, CDCl3) δ −170.53 (dd, J=4.95, 1.32, 1F). treated with silica gel (5 g SiO2/1 g of compound) an even mix to air dry The silica gel was transferred to a fritted funnel eluted with DCM until no more product The filtrate was concentrated