[(E)-4-bromobut-2-enoxy]methylbenzene

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

Procedure: A solution of 10.8 ml of benzyl alcohol (103 mmol), 3.16 g of tetrabutylammonium bisulfate (58.5 mmol) and 8.63 g of sodium hydroxide (840 mmol) in water (45.6 ml) was added to a solution of 20.0 g of trans-1,4-dibromo-2-butene (94.7 mmol) in methylene chloride (80 ml) at room temperature, and the mixture was stirred for two days. The reaction mixture was diluted with 300 ml of water, followed by extraction with methylene chloride. Then, the organic layer was washed with water and brine and dried over anhydrous magnesium sulfate. After filtration, the solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (elution solvent:n-hexane/ethyl acetate=20/1) to obtain 10.9 g of the title compound (yield: 48%). followed by extraction with methylene chloride Then, the organic layer was washed with water and brine dried over anhydrous magnesium sulfate After filtration the solvent was evaporated under reduced pressure the residue was purified by silica gel column chromatography (elution solvent:n-hexane/ethyl acetate=20/1)

Conditions: temp:-40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 165 ml of a solution of sodium bis(trimethylsilyl)amide in n-hexane (1.03 mol/l) (169 mmol) was added to a solution of 37.0 g of (S)-4-benzyl-3-pentanoyloxazolidin-2-one obtained in Reference Example 6 (142 mmol) in tetrahydrofuran (330 ml) under a nitrogen atmosphere and at −78° C. over 45 minutes, and the mixture was stirred at the same temperature for 30 minutes. Then, a solution of 35.8 g of [(E)-4-bromobut-2-enyloxymethyl]benzene obtained in Reference Example 4 (148 mmol) in tetrahydrofuran (80 ml) was added to the solution obtained above over 30 minutes, and the mixture was stirred at the same temperature for 30 minutes. Thereafter, the mixture was raised to −40° C. and further stirred for four hours. 90 ml of an ammonium chloride aqueous solution was added to the reaction mixture, and the mixture was further stirred at room temperature for one hour. The reaction mixture was concentrated under reduced pressure and diluted with 500 ml of water, followed by extraction with ethyl acetate. Then, the organic layer was washed with water and brine and dried over anhydrous magnesium sulfate. After filtration, the solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (elution solvent:n-hexane/ethyl acetate=7/1-2/1) to obtain 47.3 g of the title compound (yield: 79%). was added to the solution obtained above over 30 minutes the mixture was stirred at the same temperature for 30 minutes further stirred for four hours the mixture was further stirred at room temperature for one hour The reaction mixture was concentrated under reduced pressure diluted with 500 ml of water followed by extraction with ethyl acetate Then, the organic layer was washed with water and brine dried over anhydrous magnesium sulfate After filtration the solvent was evaporated under reduced pressure the residue was purified by silica gel column chromatography (elution solvent:n-hexane/ethyl acetate=7/1-2/1)

Conditions: temp:-40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 164 ml of a solution of sodium bis(trimethylsilyl)amide in n-hexane (1.03 mol/l) (169 mmol) was added to a solution of 35.3 g of (S)-4-benzyl-3-butyryloxazolidin-2-one obtained in Reference Example 5 (141 mmol) in tetrahydrofuran (330 ml) under a nitrogen atmosphere and at −78° C. over 45 minutes, and the mixture was stirred at the same temperature for 30 minutes. Then, a solution of 35.6 g of [(E)-4-bromobut-2-enyloxymethyl]benzene obtained in Reference Example 4 (148 mmol) in tetrahydrofuran (80 ml) was added to the solution obtained above over 30 minutes, and the mixture was stirred at the same temperature for 30 minutes. Thereafter, the mixture was raised to −40° C. and further stirred for four hours. 100 ml of a saturated ammonium chloride aqueous solution was added to the reaction mixture, and the mixture was further stirred at room temperature for one hour. The reaction mixture was concentrated under reduced pressure and diluted with 500 ml of water, followed by extraction with ethyl acetate. Then, the organic layer was washed with water and brine and dried over anhydrous magnesium sulfate. After filtration, the solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (elution solvent:n-hexane/ethyl acetate=7/1-2/1) to obtain 46.4 g of the title compound (yield: 81%). was added to the solution obtained above over 30 minutes the mixture was stirred at the same temperature for 30 minutes further stirred for four hours the mixture was further stirred at room temperature for one hour The reaction mixture was concentrated under reduced pressure diluted with 500 ml of water followed by extraction with ethyl acetate Then, the organic layer was washed with water and brine dried over anhydrous magnesium sulfate After filtration the solvent was evaporated under reduced pressure the residue was purified by silica gel column chromatography (elution solvent:n-hexane/ethyl acetate=7/1-2/1)

Conditions: temp:-40.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 164 ml of a solution of sodium bis(trimethylsilyl)amide in n-hexane (1.03 mol/l) (169 mmol) was added to a solution of 32.9 g of (S)-4-benzyl-3-propionyloxazolidin-2-one (141 mmol) in tetrahydrofuran (330 ml) under a nitrogen atmosphere and at −78° C. over 45 minutes, and the mixture was stirred at the same temperature for 30 minutes. Then, a solution of 35.5 g of [(E)-4-bromobut-2-enyloxymethyl]benzene obtained in Reference Example 4 (148 mmol) in tetrahydrofuran (80 ml) was added to the solution over 30 minutes, and the mixture was stirred at the same temperature for 30 minutes. Thereafter, the mixture was raised to −40° C. and further stirred for four hours. 100 ml of a saturated ammonium chloride aqueous solution was added to the reaction mixture, and the mixture was further stirred at room temperature for one hour. The reaction mixture was concentrated under reduced pressure and diluted with 500 ml of water, followed by extraction with ethyl acetate. Then, the organic layer was washed with water and brine and dried over anhydrous magnesium sulfate. After filtration, the solvent was evaporated under reduced pressure, and the residue was purified by silica gel column chromatography (elution solvent:n-hexane/ethyl acetate=7/1-2/1) to obtain 37.9 g of the title compound (yield: 69%). was added to the solution over 30 minutes the mixture was stirred at the same temperature for 30 minutes further stirred for four hours the mixture was further stirred at room temperature for one hour The reaction mixture was concentrated under reduced pressure diluted with 500 ml of water followed by extraction with ethyl acetate Then, the organic layer was washed with water and brine dried over anhydrous magnesium sulfate After filtration the solvent was evaporated under reduced pressure the residue was purified by silica gel column chromatography (elution solvent:n-hexane/ethyl acetate=7/1-2/1)

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

Procedure: To a solution of trans-1,4-dibromobut-2-ene (20.0 g, 93.5 mmol), benzyl alcohol (10.6 mL, 102.9 mmol), and tetrabutylammonium hydrogensulfate (3.17 g, 9.35 mmol) in dichloromethane (80 mL) were added sodium hydroxide (33.7 g, 841 mmol) in water and the resulting mixture was stirred at room temperature for 24 hours. It was diluted with water and extracted with diethyl ether. The combined organic extracts were dried over anhydrous sodium sulfate and concentrated under reduced pressure. The crude product was purified using flash column chromatography to yield 10.8 g of trans-4-benzyloxy-1-bromo-2-butene; 1H NMR (400 MHz, CDCl3) δ ppm 3.98 (d, 2H, J=7.3 Hz) 4.04 (d, 2H, J=4.4 Hz) 4.54 (s, 2H) 5.82-6.08 (m, 2H) 7.25-7.45 (m, 5H). extracted with diethyl ether The combined organic extracts were dried over anhydrous sodium sulfate concentrated under reduced pressure The crude product was purified