Magnesium Bromide → 6,7-dihydro-4H-thieno[3,2-c]pyran

Participants

Reaction Steps

61.2 g of 2-(2-methoxymethoxyethyl)thiophene obtained in Example 19 and 130.8 g of magnesium bromide were added to 850 mL of dichloromethane, and the resulting mixture was refluxed for 2 hours. The reaction product solution was cooled to room temperature and concentrated by evaporation under reduced pressure. To the residue, 500 mL of water and 800 mL of n-hexane were added, and the resulting mixture was stirred for 5 minutes. Aqueous layer was discarded, and the organic layer was washed twice with 300 mL portions of water, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was distilled under reduced pressure to obtain 40.7 g (yield of 82%) of the title compound, of which analysis data were the same as obtained in Example 14.

Provenance & Evidence