C(ON=O)(C)(C)C.N[C:9]1[C:21]([Br:22])=[CH:20][C:12]2[O:13][C:14]3[CH:19]=[CH:18][CH:17]=[CH:16][C:15]=3[C:11]=2[C:10]=1[Br:23].CCOCC>CN(C=O)C>[Br:23][C:10]1[C:11]2[C:15]3[CH:16]=[CH:17][CH:18]=[CH:19][C:14]=3[O:13][C:12]=2[CH:20]=[C:21]([Br:22])[CH:9]=1To a solution of t-butylnitrite (0.89 ml, 7.2 mmol) dissolved in 10 ml of DMF at 50° C. was added dropwise a solution of 2-amino-1,3-dibromodibenzofuran 17 (1.0 g, 2.9 mmol) in 10 ml of DMF with nitrogen evolution. After stirring at 50° C. for 1 hour the reaction was diluted into ether and washed successively with H2O and saturated NaCl. Drying over MgSO4 and evaporation gave 1.1 g of a red solid which was purified by flash chromatography through 100 g of silica gel (20% methylene chloride: hexane) yielding 650 mg (68%) of the title compound as a pale orange solid.
Wird geladen…
