6,7-dihydro-4H-thieno[3,2-c]pyran → 2-(2-Bromoethyl)-3-(bromomethyl)thiophene

Beteiligte Stoffe

Reaktionsschritte

To a solution of 9.5 g of triphenylphosphine dibromide dissolved in 50 mL of acetonitrile, 2 g of 6,7-dihydro-4H-thieno[3,2-c]pyrane obtained in Example 14 was added, and the resulting mixture was refluxed for 8 hours. The reaction product solution was concentrated by evaporation under reduced pressure. To the residue, 5 mL of ethyl acetate and then 15 mL of n-hexane were added. The resulting mixture was stirred for 1 hour at room temperature and 2 hours at below 5° C., filtered, and concentrated under reduced pressure. The residue was subjected to a silica gel column chromatography (eluent, n-hexane:ethyl acetate=10:1) to obtain 3.3 g (yield of 80%) of the title compound as a yellowish oil, of which analysis data were the same as obtained in Example 7.

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