2,2-二甲基-3H-1-苯并呋喃-6-甲醛

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 18.7 g of 2-bromopropane in 30 ml of absolute tetrahydrofuran are added dropwise to 3.6 g of Mg filings in 15 ml of absolute tetrahydrofuran. The mixture is stirred under reflux for 1 hour and is then cooled to 5°-10° C. At this temperature, 23 g of 2,2-dimethyl-2,3-dihydrobenzofuran-6-aldehyde in 100 ml of absolute tetrahydrofuran are added dropwise. The reaction mixture is stirred overnight and is then cautiously decomposed with a cold saturated ammonium chloride solution and a few milliliters of 10% strength hydrochloric acid, sufficient to dissolve the precipitate. The mixture is then extracted three times by shaking with ether and the combined ether extracts are washed with sodium bisulfate solution, sodium bicarbonate solution and water, dried over sodium sulfate and concentrated under reduced pressure. 19.5 g of 2,2-dimethyl-2,3-dihydrobenzofuran-6-yl-(α-isopropyl)-carbinol are obtained in the form of a yellowish oil, which is sufficiently pure for the subsequent reactions. (Yield 68%). under reflux for 1 hour is then cooled to 5°-10° C The reaction mixture is stirred overnight sufficient to dissolve the precipitate The mixture is then extracted three times by shaking with ether the combined ether extracts are washed with sodium bisulfate solution, sodium bicarbonate solution and water dried over sodium sulfate concentrated under reduced pressure