1-(2,2-Dibromovinyl)-4-methoxybenzene

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1-(2,2-dibromovinyl)-4-methoxybenzene (17.38 g, 59.5 mmol) prepared in Reference Synthetic Example 1 was dissolved in tetrahydrofuran (230 ml) in nitrogen atmosphere, and a 2.59 mol/l n-butyllithium/hexane solution was dropwise added at −78° C. After the dropwise addition, the solution was returned to 0° C. and stirred for 90 minutes, and then cooled to −78° C. again, and crushed dry ice was added. After stirring for 30 minutes, water was added to the solution and the solution was concentrated under reduced pressure. The residue was diluted with diethyl ether, and extracted with a 1 mol/l sodium hydroxide aqueous solution twice. The obtained aqueous layer was acidified (pH=1) with hydrochloric acid and extracted with ethyl acetate twice. The obtained organic layer was washed with water and a saturated salt solution, dried over anhydrous sodium sulfate, subjected to filtration and concentrated under reduced pressure to give the desired compound (4-methxoyphenyl)propionic acid (9.73 g, 93%) as crude crystals. After the dropwise addition was returned to 0° C. was added After stirring for 30 minutes the solution was concentrated under reduced pressure The residue was diluted with diethyl ether extracted with a 1 mol/l sodium hydroxide aqueous solution twice extracted with ethyl acetate twice The obtained organic layer was washed with water a saturated salt solution, dried over anhydrous sodium sulfate subjected to filtration concentrated under reduced pressure

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Triphenylphosphine (57.8 g, 220 mmol) was dissolved in dichromomethane (200 ml) in nitrogen atmosphere, and carbon tetrabromide (36.5 g, 110 mmol) was added little by little under cooling with ice, followed by stirring for 30 minutes. Then, p-anisic aldehyde (10.0 g, 73.4 mmol) was dropwise added under cooling with ice, followed by stirring for 10 minutes. The reaction solution was subjected to filtration, silica gel (50 g) was added to the filtrate, and the filtrate was concentrated under reduced pressure to dryness, and the resulting product was purified by silica gel column chromatography (hexane:ethyl acetate=20:1) to give the desired compound 1-(2,2-dibromovinyl)-4-methoxybenzene (21.4 g, quant.) as pale yellow solid. was added little by little under cooling with ice under cooling with ice by stirring for 10 minutes The reaction solution was subjected to filtration, silica gel (50 g) was added to the filtrate the filtrate was concentrated under reduced pressure to dryness the resulting product was purified by silica gel column chromatography (hexane:ethyl acetate=20:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Triphenylphosphine (57.8 g, 220 mmol) was dissolved in dichromomethane (200 ml) in nitrogen atmosphere, and carbon tetrabromide (36.5 g, 110 mmol) was added little by little under cooling with ice, followed by stirring for 30 minutes. Then, p-anisic aldehyde (10.0 g, 73.4 mmol) was dropwise added under cooling with ice, followed by stirring for 10 minutes. The reaction solution was subjected to filtration, silica gel (50 g) was added to the filtrate, and the filtrate was concentrated under reduced pressure to dryness, and the resulting product was purified by silica gel column chromatography (hexane:ethyl acetate=20:1) to give the desired compound 1-(2,2-dibromovinyl)-4-methoxybenzene (21.4 g, quant.) as pale yellow solid. was added little by little under cooling with ice under cooling with ice by stirring for 10 minutes The reaction solution was subjected to filtration, silica gel (50 g) was added to the filtrate the filtrate was concentrated under reduced pressure to dryness the resulting product was purified by silica gel column chromatography (hexane:ethyl acetate=20:1)

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1-(2,2-dibromovinyl)-4-methoxybenzene (17.38 g, 59.5 mmol) prepared in Reference Synthetic Example 1 was dissolved in tetrahydrofuran (230 ml) in nitrogen atmosphere, and a 2.59 mol/l n-butyllithium/hexane solution was dropwise added at −78° C. After the dropwise addition, the solution was returned to 0° C. and stirred for 90 minutes, and then cooled to −78° C. again, and crushed dry ice was added. After stirring for 30 minutes, water was added to the solution and the solution was concentrated under reduced pressure. The residue was diluted with diethyl ether, and extracted with a 1 mol/l sodium hydroxide aqueous solution twice. The obtained aqueous layer was acidified (pH=1) with hydrochloric acid and extracted with ethyl acetate twice. The obtained organic layer was washed with water and a saturated salt solution, dried over anhydrous sodium sulfate, subjected to filtration and concentrated under reduced pressure to give the desired compound (4-methxoyphenyl)propionic acid (9.73 g, 93%) as crude crystals. After the dropwise addition was returned to 0° C. was added After stirring for 30 minutes the solution was concentrated under reduced pressure The residue was diluted with diethyl ether extracted with a 1 mol/l sodium hydroxide aqueous solution twice extracted with ethyl acetate twice The obtained organic layer was washed with water a saturated salt solution, dried over anhydrous sodium sulfate subjected to filtration concentrated under reduced pressure

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Triphenylphosphine (57.8 g, 220 mmol) was dissolved in dichromomethane (200 ml) in nitrogen atmosphere, and carbon tetrabromide (36.5 g, 110 mmol) was added little by little under cooling with ice, followed by stirring for 30 minutes. Then, p-anisic aldehyde (10.0 g, 73.4 mmol) was dropwise added under cooling with ice, followed by stirring for 10 minutes. The reaction solution was subjected to filtration, silica gel (50 g) was added to the filtrate, and the filtrate was concentrated under reduced pressure to dryness, and the resulting product was purified by silica gel column chromatography (hexane:ethyl acetate=20:1) to give the desired compound 1-(2,2-dibromovinyl)-4-methoxybenzene (21.4 g, quant.) as pale yellow solid. was added little by little under cooling with ice under cooling with ice by stirring for 10 minutes The reaction solution was subjected to filtration, silica gel (50 g) was added to the filtrate the filtrate was concentrated under reduced pressure to dryness the resulting product was purified by silica gel column chromatography (hexane:ethyl acetate=20:1)