(E)-3-bromo-1-diethoxyphosphorylprop-1-ene

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

Procedure: A solution of diethyl 3-bromo-trans-1-propenylphosphonate (23.83 g.) in N,N-dimethylformamide (50 ml.) was added dropwise to a suspension of ethyl N-ethoxycarbonyloxycarbamate (19.94 g.) in N,N-dimethylformamide (100 ml.) at -25°~-30° C. in the course of 20 minutes. The reaction mixture was stirred at -20°--30° C. for an hour and at -5°~-10° C. for an hour. Subsequently, the resultant mixture was poured into a mixture of water (1 liter) and ethyl acetate (0.7 l). The ethyl acetate layer was separated and the aqueous layer was extracted twice with ethyl acetate (300 ml.). The combined ethyl acetate layer was washed with water (300 ml.), dried over magnesium sulfate and concentrated under reduced pressure to give an oily residue (28.89 g.), which was subjected to a column chromatography on silica gel [Developing solvent: a mixture of chloroform and ethyl acetate (4:1)]. The eluate was concentrated under reduced pressure to give oily diethyl 3-(N-ethoxycarbonyl-N-ethoxycarbonyloxyamino)-trans-1-propenylphosphonate (13.80 g.). The ethyl acetate layer was separated the aqueous layer was extracted twice with ethyl acetate (300 ml.) The combined ethyl acetate layer was washed with water (300 ml.) dried over magnesium sulfate concentrated under reduced pressure to give an oily residue (28.89 g.), which The eluate was concentrated under reduced pressure

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

Procedure: To a solution of diethyl trans-1-propenylphosphonate (32.04 g.) in carbon tetrachloride (320 ml.) were added N-bromosuccinimide (41.65 g.) and dibenzoylperoxide (2.8 g.). The reaction mixture was heated to reflux for 1.5 hours and stirred for 30 minutes under ice-cooling. Insoluble materials were removed off by filtration and the filtrate was concentrated under reduced pressure to give an oily residue (63.09 g.), which was subjected to a column chromatography on silicagel and eluted with chloroform. The eluates were evaporated to dryness under reduced pressure to give an oily diethyl 3-bromo-trans-1-propenylphosphonate (27.04 g.). The reaction mixture was heated to reflux for 1.5 hours cooling Insoluble materials were removed off by filtration the filtrate was concentrated under reduced pressure to give an oily residue (63.09 g.), which eluted with chloroform The eluates were evaporated to dryness under reduced pressure

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

Procedure: A solution of diethyl 3-bromo-trans-1-propenylphosphonate (23.83 g.) in N,N-dimethylformamide (50 ml.) was added dropwise to a suspension of ethyl N-ethoxycarbonyloxycarbamate (19.94 g.) in N,N-dimethylformamide (100 ml.) at -25°--30° C. in the course of 20 minutes. The reaction mixture was stirred at -20°--30° C. for an hour and at -5°--10° C. for an hour. Subsequently, the resultant mixture was poured int a mixture of water (1 liter) and ethyl acetate (0.7 l). The etheyl acetate layer was separated and the aqueous layer was extracted twice with ethyl acetate (300 ml.). The combined ethyl acetate layer was washed with water (300 ml.), dried over magnesium sulfate and concentrated under reduced pressure to give an oily residue (28.89 g.), which was subjected to a column chromatography on silica gel [Developing solvent: a mixture of chloroform and ethyl acetate (4:1)]. The eluate was concentrated under reduced pressure to give oily diethyl 3-(N-ethoxycarbonyl-N-ethoxycarbonyloxyamino)-trans-1-propenylphosphonate (13.80 g.). The etheyl acetate layer was separated the aqueous layer was extracted twice with ethyl acetate (300 ml.) The combined ethyl acetate layer was washed with water (300 ml.) dried over magnesium sulfate concentrated under reduced pressure to give an oily residue (28.89 g.), which The eluate was concentrated under reduced pressure

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

Procedure: To a solution of diethyl trans-1-propenylphosphonate (32.04 g.) in carbon tetrachloride (320 ml.) were added N-bromosuccinimide (41.65 g.) and dibenzoylperoxide (2.8 g.). The reaction mixture was heated to reflux for 1.5 hours and stirred for 30 minutes under ice-cooling. Insoluble materials were removed off by filtration and the filtrate was concentrated under reduced pressure to give an oily residue (63.09 g.), which was subjected to a column chromatography on silicagel and eluted with chloroform. The eluates were evaporated to dryness under reduced pressure to give an oily diethyl 3-bromo-trans-1-propenylphosphonate (27.04 g.). The reaction mixture was heated to reflux for 1.5 hours cooling Insoluble materials were removed off by filtration the filtrate was concentrated under reduced pressure to give an oily residue (63.09 g.), which eluted with chloroform The eluates were evaporated to dryness under reduced pressure