C[N+]1([O-])CC[O:5]CC1.Br[CH2:10][C:11]1[C:16]2[CH:17]=[CH:18][O:19][C:15]=2[CH:14]=[CH:13][C:12]=1[F:20].BrCC1C(F)=CC2C=COC=2C=1>C(#N)C>[F:20][C:12]1[C:11]([CH:10]=[O:5])=[C:16]2[CH:17]=[CH:18][O:19][C:15]2=[CH:14][CH:13]=1A solution of the N-methylmorpholine-N-oxide (13.6 g) in acetonitrile (135 ml) containing 3 Å molecular sieves (13.2 g) was stirred at room temperature overnight and cooled in ice. A solution of 4-bromomethyl-5-fluorobenzofuran and 6-bromomethyl-5-fluorobenzofuran (13.33 g) in acetonitrile (35 ml) was added and the mixture stirred at 5° for 4 h. The mixture was filtered and the filtrate evaporated to dryness. Water and ethyl acetate were added to the residue and the organic phase separated, dried and evaporated to give the mixture of aldehydes. The mixture was separated by chromatography on silica (600 g) using a mixture of ethyl acetate and hexane (1:9) as the eluant to give the title compound (A) (2.19 g);
Wird geladen…
