Use:

Alpha-methyl cinnamaldehyde is a versatile fragrance commonly used in the fragrance of cosmetics, soaps, foods, etc. the Alpha-methyl streptopropane obtained by the further reaction thereof is used as a  and also has a very good aroma. At the same time, α-methylcinnamaldehyde is also an important intermediate for the synthesis of the therapeutic drug epalrestat. As the number of diabetic patients increases, the demand for the drug increases, and the demand for intermediates also increases, and there is an urgent need to improve the process to improve quality.

 

Production

the chemical name of alpha-methylcinnamic acid is alpha-methylphenylacrolein, which is an important fine chemical intermediate and is widely used in the production of pharmaceuticals, spices and other products. At present, there are several methods for preparing alpha-methylcinnamaldehyde. 1. Benzoaldehyde and n-propanal are used as raw materials, KF/A1203 is used as a catalyst, and polyethylene glycol is a phase transfer solution to synthesize ct-methyl cinnamaldehyde. The yield is 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, PEG600 for phase transfer synthesis of a-methyl cinnamaldehyde, the yield is 54.2%, the alpha-methyl cinnamaldehyde synthesized by this method has more negative reaction, product separation It is difficult to purify; 3, using benzaldehyde and n-propionaldehyde as raw materials, ethanol as solvent, TBAB as phase transfer catalyst, synthesizing a-methyl cinnamaldehyde under alkaline medium, the yield is 59.7%, the a-form synthesized by this method The synthesis process of cinnamaldehyde is simple, but the conversion rate of the raw material reaction is low, and the negative reaction is high, resulting in low product yield.

 

Summary of the invention

the object of the present invention is to provide a method for preparing alpha-methylcinnamaldehyde, which comprises synthesizing a-formaldehyde with benzaldehyde and n-propanal in an alkaline medium and using an aqueous solution of methanol as a solvent. The cinnamaldehyde has simple method, convenient operation, low raw material cost, high yield and no pollution to the environment, and is very suitable for industrial production.

 

 

Items of analysis	Specification	Results
Color and appearance	Slightly yellow liquid	Conforms
Content	≥98.0%	98.08%
Melting	34.7~34.0C	34.9C
Arsenic content(as,mg/kg)	≤0.5	<0.5
Heavy metal assay(Pb,mg/kg)	≤1.0	<1.0
Relative density	1.030~1.040	1.0332
Refractive	1.5936	1.5936