1-Bromo-4-fluorobenzene → 2-(4-Fluorophenyl)-5-[(tetra-hydro-2-pyranyloxy)methyl]pyridine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A grignard reagent solution prepared from 1.53 g of magnesium, 10.5 g of 1-bromo-4-fluorobenzene and 70 ml of tetrahydrofuran was added dropwise at 3°-7° C. within 45 minutes to a mixture of 16.9 g of crude 2-chloro-5-[(tetrahydro-2-pyranyloxy)methyl]pyridine, 60 ml of tetrahydrofuran and 0.62 g of 1,3-bis(diphenylphosphino)-propanenickel-(II) chloride. The dark reaction mixture was stirred at 3° C. for a further 1 hr. and at room temperature for 2 hrs. and then extracted with 200 ml of diethyl ether and 120 ml of 0.5N ammonium chloride solution. The organic phase was washed neutral with water, dried over sodium sulphate, filtered and concentrated. Chromatographic purification of the residue on 230 g of silica gel with hexane/ethyl acetate (vol. 9:1) yielded 13.4 g of 2-(4-fluorophenyl)-5-[(tetra-hydro-2-pyranyloxy)methyl]pyridine as a yellowish oil.

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