反应详情

3,5-dibromo-nitro-benzene (262) (500 mg, 1.78 mmol) was dissolved in 4 mL of glacial acetic acid first. TiCl3 with 30 wt % in 2 N HCl was added gradually until the purple color disappeared even after long stirring at room temperature. The reaction was monitored by TLC. After the reaction was completed, the reaction mixture was concentrated down under vacuum to remove the acetic acid. H2O and 1 M NaOH was then added to neutralize the product followed by adding EtOAc solvent. The resulting wax like solid was filtered off under vacuum. Liquid-liquid extraction was then performed twice using EtOAc and H2O as solvents and the organic layer was dried over anhydrous Na2SO4 for 0.5 h. The drying reagent was then filtered off under vacuum and the filtrate was first dried under vacuum on rotary evaporator and then dried over oil pump overnight. 387.3 mg of the desired product (273) was obtained as a neutral base in 86.7% yield with HPLC purity of >95% (ELSD). LC-MS: m/e 250 [M+1]+, 252.

1. concentrationthe reaction mixture was concentrated down under vacuum
2. customto remove the acetic acid
3. additionH2O and 1 M NaOH was then added
4. additionby adding EtOAc solvent
5. filtrationThe resulting wax like solid was filtered off under vacuum
6. extractionLiquid-liquid extraction
7. dry with materialthe organic layer was dried over anhydrous Na2SO4 for 0.5 h
8. filtrationThe drying reagent was then filtered off under vacuum
9. customthe filtrate was first dried under vacuum on rotary evaporator
10. customdried over oil