3-hydroxybutanal

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

Procedure: Compound 494 (0.033 g, 0.09 mmol) was suspended in MeOH (1 mL). 3-Hydroxy-butyraldehyde (0.023 g, 0.27 mmol) and NaCN(BH3) (0.055 g, 0.88 mmol) were added. The suspension was stirred at room temperature for 18 h. 3-Hydroxy-butyraldehyde (0.023 g, 0.27 mmol) and NaCN(BH3) (0.055 g, 0.88 mmol) were added again and the suspension was stirred at room temperature for 24 h. The reaction mixture was concentrated in vacuo. The residue was dissolved in EtOAc and the organic phase was washed with brine. The water phase was extracted with EtOAc and the combined organic phases were dried (MgSO4), filtered and concentrated in vacuo. The crude product was purified by flash chromatography using MeOH/CH2Cl2 1:50 as the eluent. This afforded the title compound as oil. 13C NMR (CDCl3) δ 196.7, 159.0 (dd), 155.4 (dd), 147.3, 146.0, 139.6, 135.0, 133.5, 132.0, 129.9, 126.7, 124.6 (dd), 124.0 (dd), 116.3, 115.9, 114.6, 112.8, 111.6 (dd), 104.9 (dd), 67.5, 42.1, 38.0, 24.0, 19.4 the suspension was stirred at room temperature for 24 h The reaction mixture was concentrated in vacuo The residue was dissolved in EtOAc the organic phase was washed with brine The water phase was extracted with EtOAc the combined organic phases were dried (MgSO4) filtered concentrated in vacuo The crude product was purified by flash chromatography

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

Procedure: Compound 494 (0.033 g, 0.09 mmol) was suspended in MeOH (1 mL). 3-Hydroxy-butyraldehyde (0.023 g, 0.27 mmol) and NaCN(BH3) (0.055 g, 0.88 mmol) were added. The suspension was stirred at room temperature for 18 h. 3-Hydroxy-butyraldehyde (0.023 g, 0.27 mmol) and NaCN(BH3) (0.055 g, 0.88 mmol) were added again and the suspension was stirred at room temperature for 24 h. The reaction mixture was concentrated in vacuo. The residue was dissolved in EtOAc and the organic phase was washed with brine. The water phase was extracted with EtOAc and the combined organic phases were dried (MgSO4), filtered and concentrated in vacuo. The crude product was purified by flash chromatography using MeOH/CH2Cl2 1:50 as the eluent. This afforded the title compound as oil. 13C NMR (CDCl3) δ 196.7, 159.0 (dd), 155.4 (dd), 147.3, 146.0, 139.6, 135.0, 133.5, 132.0, 129.9, 126.7, 124.6 (dd), 124.0 (dd), 116.3, 115.9, 114.6, 112.8, 111.6 (dd), 104.9 (dd), 67.5, 42.1, 38.0, 24.0, 19.4 the suspension was stirred at room temperature for 24 h The reaction mixture was concentrated in vacuo The residue was dissolved in EtOAc the organic phase was washed with brine The water phase was extracted with EtOAc the combined organic phases were dried (MgSO4) filtered concentrated in vacuo The crude product was purified by flash chromatography

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

Procedure: A mixture of 88 g of β-hydroxybutyraldehyde and 150 g of diethyl ketone is added dropwise in the course of one hour to a mixture of 250 g of diethyl ketone, 80 g of isopropanol and 5 g of sodium hydroxide powder which is boiling under reflux. The whole is boiled for another hour under reflux. Neutralization is effected with glacial acetic acid and the aqueous phase is separated. The organic layer is fractionated. 65 g of 2,5,6-trimethyl-2-cyclohexen-1-one having a boiling point of 74° to 76° C. at 12 mm Hg is obtained. The yield is 47% with reference to β-hydroxybutyraldehyde. under reflux The whole is boiled for another hour under reflux the aqueous phase is separated

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

Procedure: A mixture of 88 g of β-hydroxybutyraldehyde and 150 g of diethyl ketone is added dropwise in the course of one hour to a mixture of 250 g of diethyl ketone, 80 g of isopropanol and 5 g of sodium hydroxide powder which is boiling under reflux. The whole is boiled for another hour under reflux. Neutralization is effected with glacial acetic acid and the aqueous phase is separated. The organic layer is fractionated. 65 g of 2,5,6-trimethyl-2-cyclohexen-1-one having a boiling point of 74° to 76° C. at 12 mm Hg is obtained. The yield is 47% with reference to β-hydroxybutyraldehyde. under reflux The whole is boiled for another hour under reflux the aqueous phase is separated

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

Procedure: Compound 494 (0.033 g, 0.09 mmol) was suspended in MeOH (1 mL). 3-Hydroxy-butyraldehyde (0.023 g, 0.27 mmol) and NaCN(BH3) (0.055 g, 0.88 mmol) were added. The suspension was stirred at room temperature for 18 h. 3-Hydroxy-butyraldehyde (0.023 g, 0.27 mmol) and NaCN(BH3) (0.055 g, 0.88 mmol) were added again and the suspension was stirred at room temperature for 24 h. The reaction mixture was concentrated in vacuo. The residue was dissolved in EtOAc and the organic phase was washed with brine. The water phase was extracted with EtOAc and the combined organic phases were dried (MgSO4), filtered and concentrated in vacuo. The crude product was purified by flash chromatography using MeOH/CH2Cl2 1:50 as the eluent. This afforded the title compound as oil. 13C NMR (CDCl3) δ 196.7, 159.0 (dd), 155.4 (dd), 147.3, 146.0, 139.6, 135.0, 133.5, 132.0, 129.9, 126.7, 124.6 (dd), 124.0 (dd), 116.3, 115.9, 114.6, 112.8, 111.6 (dd), 104.9 (dd), 67.5, 42.1, 38.0, 24.0, 19.4 the suspension was stirred at room temperature for 24 h The reaction mixture was concentrated in vacuo The residue was dissolved in EtOAc the organic phase was washed with brine The water phase was extracted with EtOAc the combined organic phases were dried (MgSO4) filtered concentrated in vacuo The crude product was purified by flash chromatography

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

Procedure: A mixture of 88 g of β-hydroxybutyraldehyde and 150 g of diethyl ketone is added dropwise in the course of one hour to a mixture of 250 g of diethyl ketone, 80 g of isopropanol and 5 g of sodium hydroxide powder which is boiling under reflux. The whole is boiled for another hour under reflux. Neutralization is effected with glacial acetic acid and the aqueous phase is separated. The organic layer is fractionated. 65 g of 2,5,6-trimethyl-2-cyclohexen-1-one having a boiling point of 74° to 76° C. at 12 mm Hg is obtained. The yield is 47% with reference to β-hydroxybutyraldehyde. under reflux The whole is boiled for another hour under reflux the aqueous phase is separated