Iodine → 2-(2-Cyclobutyl-6-fluoro-4-methoxyphenyl)-4,4-dimethyl-4,5-dihydro-1,3-oxazole

Beteiligte Stoffe

Reaktionsschritte

To a solution of cyclobutyl chloride (5.64 g, 62 mmol) in anhydrous tetrahydrofuran (60 mL) was added magnesium turnings (1.56 g, 65 mmol) followed by a crystal of iodine, at room temperature. The mixture was stirred at room temperature for 1 hour, followed by a further hour under reflux. A solution of the fluoro compound from preparation 2 (7.23 g, 30 mmol) in tetrahydrofuran (80 mL) was cooled in an ice-bath to 0° C., and the grignard solution (40 mL) was added dropwise over 15 minutes, the cooling bath was removed and reaction warmed to room temperature and stirred for 2 hours. Further grignard solution (10 mL) was added and the reaction stirred for a further 30 minutes. The reaction was poured into a solution of ethylenediaminetetraacetic acid disodium salt (12 g) in 1N sodium hydroxide (100 mL), and the mixture extracted with ethyl acetate (1×200 mL, 2×100 mL). The combined organic extracts were dried (MgSO4) and evaporated under reduced pressure, to afford the title compound as a pale yellow oil, 8.31 g.

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