Dimethoxymethane → 1-(6-Bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-3-methoxy-propan-1-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-(6-bromo-3-fluoro-4-triethylsilanyl-pyridin-2-yl)-ethanone (11.6 g, 33.9 mmol, example 1, step b) in dichloromethane (50 ml) was added Hünigs-base (6.21 ml, 35.6 mmol) at 0° C. followed by TMS-triflate (6.43 ml, 35.52 mmol, 1.05 eq.) under nitrogen. The reaction mixture was stirred at 0° C. for 40 minutes. Dimethoxymethane (2.71 g, 35.6 mmol) and 2,6-di-tert-butylpyridine (0.648 g, 3.39 mmol) was added drop wise at 0° C. TMS-triflate (0.61 ml, 3.39 mmol) was then added to the reaction mixture. After 30 min the cooling bath was removed and stirring was continued at rt over night (18 h). The reaction mixture was poured onto cold brine, diluted with ethyl acetate and the organic phase was washed thoroughly with 10% NaHSO4 solution, sat. sodium bicarbonate solution (saturated with NaCl) and brine, dried over sodium sulfate, filtered and evaporated. The crude product (13.52 g) was chromatographed over silica gel (320 g, cyclohexane/ethyl acetate 95:5) to give the title compound as a yellow liquid: 9.18 g (72% yield).

Provenance & Evidence