ethyl 3-(2-bromophenyl)prop-2-enoate

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

Procedure: Carboethoxymethylidene triphenylphosphorane (94 g, 270 mM) was dissolved in 350 ml of methylenechloride under nitrogen. o-Bromobenzaldehyde (31.5 ml; 270 mM) was added via an addition funnel in 125 ml of methylene chloride. The solution was allowed to stand at room temperature overnight and then the solvent was removed in vacuo. The slushy residue was taken up in 10% ethyl acetate in hexane and filtered through a one-inch pad of silica gel in a 350 ml fritted funnel with one liter of 10% ethyl acetate in hexane. Solvent removal on the rotary evaporator followed by pumping overnight gave 66.3 g of an oil, ethyl o-bromocinnamate in 96% yield. The NMR indicates a 4.5 to 1 mixture of trans to cis isomers. NMR: the solvent was removed in vacuo filtered through a one-inch pad of silica gel in a 350 ml fritted funnel with one liter of 10% ethyl acetate in hexane Solvent removal on the rotary evaporator by pumping overnight

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

Procedure: Ethyl o-bromocinnamate (66.3 g; 260 mM) was dissolved in 750 ml of anhydrous toluene under nitrogen in a three-neck round bottom flask equipped with addition funnel and condensor. A toluene solution of diisobutylaluminum hydride (520 mM; 1.53M) was transferred via canula to the addition funnel and then added dropwise to the reaction mixture, which had been chilled to -78°. After the addition was completed the reaction was warmed to ambient temperature over a 1.5 hour period and quenched by the dropwise addition of 50 ml of water. Some cooling was required. The resulting emulsion was added to 640 ml of 2N aqueous hydrochloric acid. After partitioning the slightly acidic (pH 5) aqueous layer was extracted twice with ether. The combined organic fractions were dried (MgSO4), filtered (fritted funnel), and evaporated to afford an oil. The oil was chromatographed in two portions on the Waters Prep 500 equipped with two cartridges eluting with a total of two gallons of 35% ethyl acetate in hexane. This produced 33.8 g (61% yield) of o-bromocinnamylalcohol. NMR (CDCl3): δ 6.8-7.8 (m; 5H); 6.0-6.6 (AB; 1H); 4.2-4.4 (brd.; 2H); 2-2.6 (brs; 1H). equipped with addition funnel added dropwise to the reaction mixture, which had been chilled to -78° After the addition quenched by the dropwise addition of 50 ml of water The resulting emulsion was added to 640 ml of 2N aqueous hydrochloric acid After partitioning the slightly acidic (pH 5) aqueous layer was extracted twice with ether The combined organic fractions were dried (MgSO4) filtered (fritted funnel) evaporated to afford an oil The oil was chromatographed in two portions on the Waters Prep 500 equipped with two cartridges eluting with a total of two gallons of 35% ethyl acetate in hexane

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

Procedure: Carboethoxymethylidene triphenylphosphorane (94 g, 270 mM) was dissolved in 350 ml of methylenechloride under nitrogen. o-Bromobenzaldehyde (31.5 ml; 270 mM) was added via an addition funnel in 125 ml of methylene chloride. The solution was allowed to stand at room temperature overnight and then the solvent was removed in vacuo. The slushy residue was taken up in 10% ethyl acetate in hexane and filtered through a one-inch pad of silica gel in a 350 ml fritted funnel with one liter of 10% ethyl acetate in hexane. Solvent removal on the rotary evaporator followed by pumping overnight gave 66.3 g of an oil, ethyl o-bromocinnamate in 96% yield. The NMR indicates a 4.5 to 1 mixture of trans to cis isomers. the solvent was removed in vacuo filtered through a one-inch pad of silica gel in a 350 ml fritted funnel with one liter of 10% ethyl acetate in hexane Solvent removal on the rotary evaporator by pumping overnight

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

Procedure: Ethyl o-bromocinnamate (66.3 g; 260 mM) was dissolved in 750 ml of anhydrous toluene under nitrogen in a three-neck round bottom flask equipped with addition funnel and condensor. A toluene solution of diisobutylaluminum hydride (520 mM; 1.53 M) was transferred via canula to the addition funnel and then added dropwise to the reaction mixture, which had been chilled to -78°. After the addition was completed the reaction was warmed to ambient temperature over a 1.5 hour period and quenched by the dropwise addition of 50 ml of water. Some cooling was required. The resulting emulsion was added to 640 ml of 2N aqueous hydrochloric acid. After partitioning, the slightly acidic (pH 5) aqueous layer was extracted twice with ether. The combined organic fractions were dried (MgSO4), filtered (fritted funnel), and evaporated to afford an oil. The oil was chromatographed in two portions on the Waters Prep 500 equipped with two cartridges eluting with a total of two gallons of 35% ethyl acetate in hexane. This produced 33.8 g (61% yield) of o-bromocinnamylalcohol. NMR (CDCl3): δ6.8-7.8 (m; 5H); 6.0-6.6 (AB; 1H); 4.2-4.4 (brd.; 2H); 2-2.6 (brs; 1H). equipped with addition funnel added dropwise to the reaction mixture, which had been chilled to -78° After the addition quenched by the dropwise addition of 50 ml of water The resulting emulsion was added to 640 ml of 2N aqueous hydrochloric acid After partitioning the slightly acidic (pH 5) aqueous layer was extracted twice with ether The combined organic fractions were dried (MgSO4) filtered (fritted funnel) evaporated to afford an oil The oil was chromatographed in two portions on the Waters Prep 500 equipped with two cartridges eluting with a total of two gallons of 35% ethyl acetate in hexane

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

Procedure: Ethyl o-bromocinnamate (66.3 g; 260 mM) was dissolved in 750 ml of anhydrous toluene under nitrogen in a three-neck round bottom flask equipped with addition funnel and condensor. A toluene solution of diisobutylaluminum hydride (520 mM; 1.53M) was transferred via canula to the addition funnel and then added dropwise to the reaction mixture, which had been chilled to -78°. After the addition was completed the reaction was warmed to ambient temperature over a 1.5 hour period and quenched by the dropwise addition of 50 ml of water. Some cooling was required. The resulting emulsion was added to 640 ml of 2N aqueous hydrochloric acid. After partitioning the slightly acidic (pH 5) aqueous layer was extracted twice with ether. The combined organic fractions were dried (MgSO4), filtered (fritted funnel), and evaporated to afford an oil. The oil was chromatographed in two portions on the Waters Prep 500 equipped with two cartridges eluting with a total of two gallons of 35% ethyl acetate in hexane. This produced 33.8 g (61% yield) of o-bromocinnamylalcohol. equipped with addition funnel added dropwise to the reaction mixture, which had been chilled to -78° After the addition quenched by the dropwise addition of 50 ml of water The resulting emulsion was added to 640 ml of 2N aqueous hydrochloric acid After partitioning the slightly acidic (pH 5) aqueous layer was extracted twice with ether The combined organic fractions were dried (MgSO4) filtered (fritted funnel) evaporated to afford an oil The oil was chromatographed in two portions on the Waters Prep 500 equipped with two cartridges eluting with a total of two gallons of 35% ethyl acetate in hexane

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

Procedure: Carboethoxymethylidene triphenylphosphorane (94 g, 270 mM) was dissolved in 350 ml of methylenechloride under nitrogen. o-Bromobenzaldehyde (31.5 ml; 270 mM) was added via an addition funnel in 125 ml of methylene chloride. The solution was allowed to stand at room temperature overnight and then the solvent was removed in vacuo. The slushy residue was taken up in 10% ethyl acetate in hexane and filtered through a one-inch pad of silica gel in a 350 ml fritted funnel with one liter of 10% ethyl acetate in hexane. Solvent removal on the rotary evaporator followed by pumping overnight gave 66.3 g of an oil, ethyl o-bromocinnamate in 96% yield. The NMR indicates a 4.5 to 1 mixture of trans to cis isomers. the solvent was removed in vacuo filtered through a one-inch pad of silica gel in a 350 ml fritted funnel with one liter of 10% ethyl acetate in hexane Solvent removal on the rotary evaporator by pumping overnight

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

Procedure: Carboethoxymethylidene triphenylphosphorane (94 g, 270 mM) was dissolved in 350 ml of methylenechloride under nitrogen. o-Bromobenzaldehyde (31.5 ml; 270 mM) was added via an addition funnel in 125 ml of methylene chloride. The solution was allowed to stand at room temperature overnight and then the solvent was removed in vacuo. The slushy residue was taken up in 10% ethyl acetate in hexane and filtered through a one-inch pad of silica gel in a 350 ml fritted funnel with one liter of 10% ethyl acetate in hexane. Solvent removal on the rotary evaporator followed by pumping overnight gave 66.3 g of an oil, ethyl o-bromocinnamate in 96% yield. The NMR indicates a 4.5 to 1 mixture of trans to cis isomers. NMR: the solvent was removed in vacuo filtered through a one-inch pad of silica gel in a 350 ml fritted funnel with one liter of 10% ethyl acetate in hexane Solvent removal on the rotary evaporator by pumping overnight

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

Procedure: Ethyl o-bromocinnamate (66.3 g; 260 mM) was dissolved in 750 ml of anhydrous toluene under nitrogen in a three-neck round bottom flask equipped with addition funnel and condensor. A toluene solution of diisobutylaluminum hydride (520 mM; 1.53M) was transferred via canula to the addition funnel and then added dropwise to the reaction mixture, which had been chilled to -78°. After the addition was completed the reaction was warmed to ambient temperature over a 1.5 hour period and quenched by the dropwise addition of 50 ml of water. Some cooling was required. The resulting emulsion was added to 640 ml of 2N aqueous hydrochloric acid. After partitioning the slightly acidic (pH 5) aqueous layer was extracted twice with ether. The combined organic fractions were dried (MgSO4), filtered (fritted funnel), and evaporated to afford an oil. The oil was chromatographed in two portions on the Waters Prep 500 equipped with two cartridges eluting with a total of two gallons of 35% ethyl acetate in hexane. This produced 33.8 g (61% yield) of o-bromocinnamylalcohol. NMR (CDCl3): δ 6.8-7.8 (m; 5H); 6.0-6.6 (AB; 1H); 4.2-4.4 (brd.; 2H); 2-2.6 (brs; 1H). equipped with addition funnel added dropwise to the reaction mixture, which had been chilled to -78° After the addition quenched by the dropwise addition of 50 ml of water The resulting emulsion was added to 640 ml of 2N aqueous hydrochloric acid After partitioning the slightly acidic (pH 5) aqueous layer was extracted twice with ether The combined organic fractions were dried (MgSO4) filtered (fritted funnel) evaporated to afford an oil The oil was chromatographed in two portions on the Waters Prep 500 equipped with two cartridges eluting with a total of two gallons of 35% ethyl acetate in hexane

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

Procedure: Carboethoxymethylidene triphenylphosphorane (94 g, 270 mM) was dissolved in 350 ml of methylenechloride under nitrogen. o-Bromobenzaldehyde (31.5 ml; 270 mM) was added via an addition funnel in 125 ml of methylene chloride. The solution was allowed to stand at room temperature overnight and then the solvent was removed in vacuo. The slushy residue was taken up in 10% ethyl acetate in hexane and filtered through a one-inch pad of silica gel in a 350 ml fritted funnel with one liter of 10% ethyl acetate in hexane. Solvent removal on the rotary evaporator followed by pumping overnight gave 66.3 g of an oil, ethyl o-bromocinnamate in 96% yield. The NMR indicates a 4.5 to 1 mixture of trans to cis isomers. the solvent was removed in vacuo filtered through a one-inch pad of silica gel in a 350 ml fritted funnel with one liter of 10% ethyl acetate in hexane Solvent removal on the rotary evaporator by pumping overnight

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

Procedure: Ethyl o-bromocinnamate (66.3 g; 260 mM) was dissolved in 750 ml of anhydrous toluene under nitrogen in a three-neck round bottom flask equipped with addition funnel and condensor. A toluene solution of diisobutylaluminum hydride (520 mM; 1.53 M) was transferred via canula to the addition funnel and then added dropwise to the reaction mixture, which had been chilled to -78°. After the addition was completed the reaction was warmed to ambient temperature over a 1.5 hour period and quenched by the dropwise addition of 50 ml of water. Some cooling was required. The resulting emulsion was added to 640 ml of 2N aqueous hydrochloric acid. After partitioning, the slightly acidic (pH 5) aqueous layer was extracted twice with ether. The combined organic fractions were dried (MgSO4), filtered (fritted funnel), and evaporated to afford an oil. The oil was chromatographed in two portions on the Waters Prep 500 equipped with two cartridges eluting with a total of two gallons of 35% ethyl acetate in hexane. This produced 33.8 g (61% yield) of o-bromocinnamylalcohol. NMR (CDCl3): δ6.8-7.8 (m; 5H); 6.0-6.6 (AB; 1H); 4.2-4.4 (brd.; 2H); 2-2.6 (brs; 1H). equipped with addition funnel added dropwise to the reaction mixture, which had been chilled to -78° After the addition quenched by the dropwise addition of 50 ml of water The resulting emulsion was added to 640 ml of 2N aqueous hydrochloric acid After partitioning the slightly acidic (pH 5) aqueous layer was extracted twice with ether The combined organic fractions were dried (MgSO4) filtered (fritted funnel) evaporated to afford an oil The oil was chromatographed in two portions on the Waters Prep 500 equipped with two cartridges eluting with a total of two gallons of 35% ethyl acetate in hexane