Carbon tetrabromide → 1-(2,2-Dibromovinyl)-3,5-diethoxybenzene

Temperature

0 °C

Carbon tetrabromide (4.78 g) was dissolved in dichloroethane (14 mL), and triphenylphosphine (7.56 g) was added thereto at 0° C. After stirring at 0° C. for 5 minutes, a solution of 3,5-diethoxybenzaldehyde (1.40 g) in dichloromethane (7 mL) was added thereto, followed by stirring for 20 minutes. Without performing further treatment, the reaction mixture was purified by silica gel chromatography (developing solvent: hexane/ethyl acetate) to obtain 1-(2,2-dibromovinyl)-3,5-diethoxybenzene. The obtained compound was used for the subsequent reaction without further purification. The compound obtained above was dissolved in THF (30 mL). A 1.63 M n-butyllithium solution in hexane (10.5 mL) was added thereto at −78° C. The resulting mixture was stirred at −78° C. for 30 minutes. After adding a saturated aqueous ammonium chloride solution, the reaction mixture was subjected to extraction using ethyl acetate. The resulting organic layer was washed with a saturated sodium chloride solution, and the organic layer was then dried over anhydrous sodium sulfate. The solvent was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (developing solvent: hexane/ethyl acetate) to obtain the title compound as a colorless, oily substance (1.31 g). Physical properties: m/z [M+H]+ 191.0

1. customat 0° C
2. stirringby stirring for 20 minutes
3. customthe reaction mixture was purified by silica gel chromatography (developing solvent: hexane/ethyl acetate)

ORD record

ord-2fbc6c50f9b448a69f5a769bd0063331

Source dataset

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09108973B2