ethyl 3-cyclopropylprop-2-enoate

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

Procedure: 29.1 ml (72.8 mmol) of a 2.5 M solution of n-butyllithium in hexane were added dropwise to a solution, cooled to −40° C., of 10.2 ml (72.8 mmol) of diisopropylamine in 35 ml of abs. THF. After the end of the addition, the mixture was stirred at −40° C. for another 30 min and then cooled to −78° C., and a solution of 7.1 ml (72.8 mmol) of ethyl acetate in 10 ml of abs. THF was added dropwise. The reaction mixture was stirred at −78° C. for 30 min, and a solution of 8.50 g (60.54 mmol) of ethyl 3-cyclopropylacrylate in a little THF was then added dropwise. After 1 h at −78° C., the mixture was slowly warmed to −40° C., then to 0° C., and a saturated aqueous ammonium chloride solution was finally added. After extraction with ethyl acetate, the organic phase was washed with 1 N hydrochloric acid and sat. sodium chloride solution, dried over sodium sulphate and concentrated under reduced pressure. The crude product was purified by chromatography on silica gel (mobile phase cyclohexane/ethyl acetate 30:1→6:1). This gave 3.28 g of the target product (23.7% of theory). After the end of the addition cooled to −78° C. The reaction mixture was stirred at −78° C. for 30 min After 1 h at −78° C. the mixture was slowly warmed to −40° C. After extraction with ethyl acetate the organic phase was washed with 1 N hydrochloric acid and sat. sodium chloride solution dried over sodium sulphate concentrated under reduced pressure The crude product was purified by chromatography on silica gel (mobile phase cyclohexane/ethyl acetate 30:1→6:1)

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

Procedure: 29.1 ml (72.8 mmol) of a 2.5 M solution of n-butyllithium in hexane were added dropwise to a solution, cooled to −40° C., of 10.2 ml (72.8 mmol) of diisopropylamine in 35 ml of abs. THF. After the end of the addition, the mixture was stirred at −40° C. for another 30 min and then cooled to −78° C., and a solution of 7.1 ml (72.8 mmol) of ethyl acetate in 10 ml of abs. THF was added dropwise. The reaction mixture was stirred at −78° C. for 30 min, and a solution of 8.50 g (60.54 mmol) of ethyl 3-cyclopropylacrylate in a little THF was then added dropwise. After 1 h at −78° C., the mixture was slowly warmed to −40° C., then to 0° C., and a saturated aqueous ammonium chloride solution was finally added. After extraction with ethyl acetate, the organic phase was washed with 1 N hydrochloric acid and sat. sodium chloride solution, dried over sodium sulphate and concentrated under reduced pressure. The crude product was purified by chromatography on silica gel (mobile phase cyclohexane/ethyl acetate 30:1→6:1). This gave 3.28 g of the target product (23.7% of theory). After the end of the addition cooled to −78° C. The reaction mixture was stirred at −78° C. for 30 min After 1 h at −78° C. the mixture was slowly warmed to −40° C. After extraction with ethyl acetate the organic phase was washed with 1 N hydrochloric acid and sat. sodium chloride solution dried over sodium sulphate concentrated under reduced pressure The crude product was purified by chromatography on silica gel (mobile phase cyclohexane/ethyl acetate 30:1→6:1)

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

Procedure: At 0° C., 13.0 ml (64.85 mmol) of ethyl diethylphosphonoacetate were added dropwise to a suspension of 2.59 g (64.85 mmol) of sodium hydride (60% in mineral oil) in 110 ml of abs. THF. After 30 min, the mixture was warmed to RT and, after cooling again to 0° C., 5.3 ml (71.34 mmol) of cyclopropanecarboxaldehyde were added dropwise. After the end of the addition, the reaction mixture was warmed to RT and diluted with 35 ml of DMF. The mixture was stirred at RT overnight and then added to water. The mixture was extracted three times with ethyl acetate. The combined organic phases were concentrated under reduced pressure and the crude product was purified by filtration through silica gel (mobile phase cyclohexane/ethyl acetate 10:1→6:1). This gave 8.53 g of the target product (93.8% of theory). after cooling again to 0° C. After the end of the addition the reaction mixture was warmed to RT The mixture was extracted three times with ethyl acetate The combined organic phases were concentrated under reduced pressure the crude product was purified by filtration through silica gel (mobile phase cyclohexane/ethyl acetate 10:1→6:1)

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

Procedure: 29.1 ml (72.8 mmol) of a 2.5 M solution of n-butyllithium in hexane were added dropwise to a solution, cooled to −40° C., of 10.2 ml (72.8 mmol) of diisopropylamine in 35 ml of abs. THF. After the end of the addition, the mixture was stirred at −40° C. for another 30 min and then cooled to −78° C., and a solution of 7.1 ml (72.8 mmol) of ethyl acetate in 10 ml of abs. THF was added dropwise. The reaction mixture was stirred at −78° C. for 30 min, and a solution of 8.50 g (60.54 mmol) of ethyl 3-cyclopropylacrylate in a little THF was then added dropwise. After 1 h at −78° C., the mixture was slowly warmed to −40° C., then to 0° C., and a saturated aqueous ammonium chloride solution was finally added. After extraction with ethyl acetate, the organic phase was washed with 1 N hydrochloric acid and sat. sodium chloride solution, dried over sodium sulphate and concentrated under reduced pressure. The crude product was purified by chromatography on silica gel (mobile phase cyclohexane/ethyl acetate 30:1→6:1). This gave 3.28 g of the target product (23.7% of theory). After the end of the addition cooled to −78° C. The reaction mixture was stirred at −78° C. for 30 min After 1 h at −78° C. the mixture was slowly warmed to −40° C. After extraction with ethyl acetate the organic phase was washed with 1 N hydrochloric acid and sat. sodium chloride solution dried over sodium sulphate concentrated under reduced pressure The crude product was purified by chromatography on silica gel (mobile phase cyclohexane/ethyl acetate 30:1→6:1)

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

Procedure: At 0° C., 13.0 ml (64.85 mmol) of ethyl diethylphosphonoacetate were added dropwise to a suspension of 2.59 g (64.85 mmol) of sodium hydride (60% in mineral oil) in 110 ml of abs. THF. After 30 min, the mixture was warmed to RT and, after cooling again to 0° C., 5.3 ml (71.34 mmol) of cyclopropanecarboxaldehyde were added dropwise. After the end of the addition, the reaction mixture was warmed to RT and diluted with 35 ml of DMF. The mixture was stirred at RT overnight and then added to water. The mixture was extracted three times with ethyl acetate. The combined organic phases were concentrated under reduced pressure and the crude product was purified by filtration through silica gel (mobile phase cyclohexane/ethyl acetate 10:1→6:1). This gave 8.53 g of the target product (93.8% of theory). after cooling again to 0° C. After the end of the addition the reaction mixture was warmed to RT The mixture was extracted three times with ethyl acetate The combined organic phases were concentrated under reduced pressure the crude product was purified by filtration through silica gel (mobile phase cyclohexane/ethyl acetate 10:1→6:1)