[F:1][C:2]1([F:13])[O:6][C:5]2[CH:7]=[CH:8][C:9]([CH2:11]Br)=[CH:10][C:4]=2[O:3]1.[C-:14]#[N:15].[K+].[Br-].[K+]>O>[F:1][C:2]1([F:13])[O:6][C:5]2[CH:7]=[CH:8][C:9]([CH2:11][C:14]#[N:15])=[CH:10][C:4]=2[O:3]1To a solution of 2,2-difluoro-5-bromomethyl-1,3-benzodioxole (41.0 g) in absolute alcohol (160 ml) at 60° to 70° C a hot solution of potassium cyanide (22.1 g, 0.34 mole) in water (30 ml) is added. There is a slight exotherm and within 5 minutes potassium bromide separates out of the reaction mixture. The reaction mixture is refluxed for 1.5 hours, cooled and added to ice-water. The mixture is extracted with ether (3×100 ml), the combined extracts are washed with water (2×50 ml), dried over sodium sulfate and evaporated to afford a dark oil. Vacuum distillation yields 21.2 g of title product; b.p. 64° to 67° C (at 0.03 mm); i.r. (neat) 2255 cm-1 ; nmr (CCl4) δ 3.68 (S, 2H), 7.00 (S, 3H).
Wird geladen…
