Background and overview[1]
Anisal is miscible with ethanol and ether, soluble in acetone, benzene and chloroform, and insoluble in water. Evaporates in steam. Reacts with aniline to form CH3OC5H4CH=NC6H5, self-disproportionation produces anisic acid and anisyl alcohol in the presence of KOH, reacts with KCN to produce anisoin, reacts with PCl5 to produce α, α-dichloromethylanisole, and reacts with HNO3/H2SO4 reacts to produce 3-nitro-4-methoxybenzaldehyde and 3,5-dinitro-4- Methoxybenzaldehyde. It is an odorous fungal metabolite.
Purpose[2-4]
Anisaldehyde is one of the main components in star anise oil. Anisaldehyde has the aroma of hawthorn flowers and a long-lasting fragrance. It also has strong antioxidant properties and is widely used in the preparation of daily chemical flavors and food flavors, and in the pharmaceutical industry. Amoxicillin is widely used in the manufacture of antimicrobial drugs. It can be used as an excellent brightener as a DE additive for cyanide-free zinc plating in the electroplating industry. In agriculture, anisaldehyde can be used as a pesticide, pesticide additive and biological growth inhibitor. wait.
1) Synthesis of raspberry ketone, which is characterized in that anisyl acetone is prepared from the natural equivalent anisaldehyde through Claisen-Schmidt condensation, hydrogenation reduction and other processes, and is demethylated and followed up at a temperature of 50-80°C. Raspberry ketone is prepared through crystallization, recrystallization and other processes. The process of the invention is simple and easy to implement. It uses natural equivalent anisaldehyde as raw material and can prepare raspberry ketone through a three-step process. The process conditions are mild, the reaction yield can reach 67.5%, and the hydrogenation catalyst can be recycled 30 times. above. The structure of the synthetic product has been characterized using analytical methods such as infrared spectroscopy, nuclear magnetic resonance and mass spectrometry. The product has a more refreshing fragrance and longer lasting fragrance than other synthetic raspberry ketone flavors.
2) Acetalization reaction occurs between sodium alginate and p-methoxybenzaldehyde (also known as anisaldehyde) under acid catalysis to obtain hydrophobically modified sodium alginate, and prepare it into a gel. The results of product analysis using fluorescence, transmission electron microscopy, scanning electron microscopy, ultraviolet, and thermal analysis showed that anisaldehyde successfully reacted with sodium alginate. The gel can be used as a drug carrier to embed and release bovine serum albumin. It was found that the drug loading rate and sustained release performance of the modified product were improved compared to unmodified sodium alginate. The product of the present invention can be used as a drug carrier material in the medical field.
Preparation[2,5]
Method 1: Preparation method of anisaldehyde, including the following steps:
(1) Mix anethole, organic solvent and water with a mass ratio of 20:(20~100):(1~20) to obtain reaction raw materials; add the reaction raw materials to the bubbling reaction tower, and control the reaction temperature at 20～30℃, pass ozone (O3) and Oxygen (O2) mixed gas is used to carry out ozonation reaction; after the ozonation reaction is completed, continue to pass oxygen for 15min to 30min to drive out excess ozone and obtain an ozonation reaction liquid; the ozone and oxygen are mixed The mass percentage of ozone in the gas is 2% to 8%;
(2) Heat the anhydrous sodium sulfite solution to 60-80°C, and add the ozonation reaction solution dropwise to perform the reduction reaction. The mass ratio of the ozonation reaction solution and the anhydrous sodium sulfite solution is 1:1.5-2.5; dropwise After the addition is completed, continue the reaction for 30 to 60 minutes, cool, let stand, and separate the liquids to obtain crude anisaldehyde; distill the crude anisaldehyde to remove the organic solvent to obtain anisaldehyde product.
Method 2: A method for preparing anisaldehyde by microwave-assisted acid-catalyzed hydrogen peroxide oxidation of anethole to produce anisaldehyde, including the following steps: (1) Add the solvent absolute ethanol, acid catalyst and 5~30% hydrogen peroxide solution into anethole and put it into a microwave reactor; (2) React for 10 to 120 minutes under microwave power of 24 to 300W; (3) Concentrate the reaction solution to remove ethanol and cool to room temperature, add ferrous sulfate solution to starch potassium iodide Just make sure the test paper does not change blue; (4) Steam distillation to evaporate the volatile oil; (5) Dry with anhydrous sodium sulfate desiccant and centrifuge to obtain anisaldehyde. This method effectively solves the existing industrial method of preparing anisaldehyde with low yield, complex operation and “three wastes”.The problem of difficult dyeing treatment, serious equipment corrosion, high cost and high energy consumption has improved the yield of anisaldehyde, reduced the production cost, and provided a technically simpler and more environmentally friendly production method for the preparation of anisaldehyde from anethole. .
Main reference materials
[1] Compound Dictionary
[2] CN200810073967.7 Method for preparing anisaldehyde by microwave-assisted acid-catalyzed oxidation of anethole with hydrogen peroxide
[3] CN200910114390.4 A new method for synthesizing raspberry ketone from the natural equivalent anisaldehyde
[4] CN201110262863.2 Preparation method of anisaldehyde-modified sodium alginate and gel microspheres thereof
[5] CN200910214322.5 A kind of preparation method of anisaldehyde
