N1C(C)=CC=CC=1C.[Br:9][C:10]1[CH:11]=[C:12]([N+:20]([O-:22])=[O:21])[C:13]([O:18][CH3:19])=[C:14]([CH:17]=1)[CH2:15]O.[Br-:23].[Li+].CS(OS(C)(=O)=O)(=O)=O>O1CCCC1>[Br:9][C:10]1[CH:11]=[C:12]([N+:20]([O-:22])=[O:21])[C:13]([O:18][CH3:19])=[C:14]([CH:17]=1)[CH2:15][Br:23]
2,6-Lutidine (10.5 mL) was added to a stirring solution of 5-bromo-2-methoxy-3-nitrobenzyl alcohol (13.6 g) and lithium bromide (11.75 g) in anhydrous tetrahydrofuran (200 mL) at 0° C. A solution of methanesulfonic anhydride (11.8 g) in anhydrous tetrahydrofuran (20 mL) was added dropwise. The resulting mixture was left to stir at room temperature for 16 h. It was partitioned between diethyl ether (250 mL) and saturated sodium hydrogen carbonate (150 mL). The organic layer was dried (sodium sulfate) and evaporated in vacuo. Silica gel chromatography of the crude residue eluting with diethyl ether in petroleum ether gave the title compound (20 g) as an amber oil.
Wird geladen…
