I tried the method I proposed above
1-(2,4-Dimethoxyphenyl)-2-nitropropene, 6 g (27 mmol)
NaBH
4, 1,2 g (32 mmol)
Aliquat 336
NaOH
Water
Toluene
Sulfuric acid
To a solution of 1,2 g sodium borohydride in 20 ml water containing 20 mg NaOH, I added 20 ml toluene, 6 g 1-(2,4-dimethoxyphenyl)-2-nitropropene and 0,5 g Aliquat 336. The mixture was violently stirred for 20 minutes at 30°C. The color had then changed from the initial dark yellow to nearly colorless. Dilute acetic acid was then added until gas evolution ceased and the aqueous phase discarged.
To the toluene solution of 1-(2,4-dimethoxyphenyl)-2-nitropropane and aliquat 336 was then added 2,5 molar equivalents NaOH (67 mmol, 2,7 g) dissolved in 20 ml water, and the mixture was then stirred violently for 20 minutes while the temperature was kept at 60°C. The toluene solution was then separated from the aqueous solution now containing the sodium salt of 1-(2,4-dimethoxyphenyl)-2-nitropropane. This aqueous solution was then added dropwise to diluted sulfuric acid (130 mmol, 12,7g in 100 ml water) with good stirring while the temperature was kept at 60° by heating.
The acidic solution became cloudy immediately upon adding the alkaline solution and some oily drops became apparent. I also noticed the ketone smell. When all alkaline solution was added the solution resembled milk with a yellow oil floating on the surface. The heating and stirring was continued for 10 minutes. This caused the milkiness to dissapear and gave a clear solution with the ketone floating on the surface. The ketone was isolated by extraction with toluene (2x20 ml), the combined extracts was dried over MgSO
4 and the solvent removed by distillation under reduced pressure. This left 2,8 g 1-(2,4-dimethoxyphenyl)-2-propanone (14 mmol, 51%).
Higher yields can be achieved if more nitroalkane can be dragged out of the toluene solution, as I suspect there is still more left in there. But hey, it's a good start!!