3-Oxo-2-(2-phenylhydrazono)butanoic acid ethyl ester synthesis
- Product Name:3-Oxo-2-(2-phenylhydrazono)butanoic acid ethyl ester
- CAS Number:10475-63-5
- Molecular formula:C12H14N2O3
- Molecular Weight:0
Yield:10475-63-5 95%
Reaction Conditions:
Stage #1: anilinewith hydrogenchloride;sodium nitrite in water at -5 - 20; for 0.5 h;
Stage #2: ethyl acetoacetatewith sodium acetate in ethanol;water at 0; for 2 h;
Steps:
5 ethyl-3-oxo-2-(phenylhydrazono)butyrate(i)
To a 500 mL three-necked flask was added 50 mL of water and 200 mL of an ethanol mixed solution, Add anhydrous sodium acetate stirring to dissolve after adding ethyl acetoacetate, room temperature stirring 2h, spare. aniline and 50 mL of water were added to another 250 mL three-necked flask, concentrated hydrochloric acid was added dropwise at room temperature, drop after the drop to -5 °C drop of aqueous sodium nitrite solution to keep the solution temperature below 0 °C, Drop after the reaction at 0°C for 30min, if the solution is a solid added a small amount of water, So that the diazonium salt solution remains clear.The mixed solution of ethyl acetoacetate was cooled to below the solution temperature at 0 °C, mechanically stirred, The above-mentioned diazonium salt solution is slowly added dropwise to keep the solution temperature below 0 ° C. With the drop of the diazonium salt solution, there will be a large amount of yellow solid in the reaction solution. After adding 100 mL of water, 0°C below the reaction 2h. The yellow solid obtained in the above reaction solution was suction-filtered, and the filter cake was washed with water and dried. To obtain 17g product, the yield of about 95% or more.
References:
CN107253964,2017,A Location in patent:Paragraph 0192; 0193
