Views:72 Author:Site Editor Publish Time: 2019-04-19 Origin:Site
At present, the major laboratories mainly synthesize alpha-methyl cinnamaldehyde from benzaldehyde and butyraldehyde. The amount of catalyst, molar ratio of raw materials and reaction time have great influence on the yield of alpha-methylcinnamaldehyde. The optimized conditions are as follows: ethanol as solvent, tetrabutylammonium bromide as catalyst, n (benzaldehyde): n (propionaldehyde): n (catalyst) 1.4:1:0.015, reaction at room temperature for 6 hours, yield up to 84.6%, an excess of benzaldehyde can be recovered.
Some other methods of synthesizing alpha-methyl cinnamaldehyde are as follows:
1. Using benzaldehyde and n-propionaldehyde as raw materials, KF/A1203 as catalyst, polyethylene glycol as phase transfer solution, and synthesis of ct-methyl cinnamaldehyde, the yield was 78.9%. The yield of alpha-methylcinnamaldehyde synthesized by the method is high, and the process is relatively simple, but the preparation of the catalyst used is complicated, expensive, and has a little pollution to the environment, and the recycling process is cumbersome.
2. Using benzaldehyde and n-propionaldehyde as raw materials, ethanol as solvent, PEG400 and PEG600 as phase transfer to synthesize alpha-methylcinnamaldehyde, the yield is 54.2%. The alpha-methylcinnamaldehyde synthesized by this method has more negative reaction and product separation. It is difficult to purify.
3. Using benzaldehyde and n-propanal as raw materials, ethanol as solvent, TBAB as phase transfer catalyst, synthesizing a-methyl cinnamaldehyde under alkaline medium, the yield is 59.7%. The alpha-methyl cinnamaldehyde synthesized by this method The synthesis process is simple, but the conversion rate of the raw material reaction is low, and the negative reaction is high, resulting in a low product yield.
Potential health effects:
Inhalation May be harmful if inhaled. May cause respiratory irritation.
Ingestion is harmful if taken.
Skin absorption through the skin can be harmful. May cause skin irritation.
Eyes may cause eye irritation.