Difluoroacetic acid → 1,1-Difluoro-2-hexanone

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a 3 liter, three-neck, round bottom flask, equipped with a magnetic stirrer, a dropping funnel filled with 39.9 g. of difluoroacetic acid and 200 ml. of ether, and a rubber septum is added 1350 ml. of ether. After cooling in a dry ice-acetone bath under nitrogen, one mole of n-butyl lithium (2.2 M, hexane) is added via a double tip needle. The difluoroacetic acid solution is slowly added to the cooled n-butyl lithium solution via the dropping funnel over 3 hours. The thick mixture is stirred at -78° C. for one hour and then quenched by pouring into a mixture of one liter of 4 N hydrochloric acid and one liter of ice, divided into three flasks, with stirring. The organic layers are combined and washed with water and brine. The 1500 ml. of solution is distilled at atmospheric pressure in a water bath. After the forerun is collected, the residue is fractionally distilled giving 18.8 g. (b.p. 100°-110° C.) of product that is 75% real.

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