A kind of synthetic method of phenolic etherification

Abstract

The invention provides a method for synthesizing phenols by etherifying. The method comprises the following steps: adding a phenolic substance, a basic catalyst and dimethyl carbonate to a reflux condensation device; putting the device into a microwave far-infrared reactor; carrying out heating reaction, then washing by 5% NaOH solution, washing with water, skimming, bathing in ice, filtering, and recrystallizing to obtain a target product. Compared with the prior art, phenol etherification is achieved by using an infrared-microwave compound method, a high-toxicity substance, namely dimethyl sulfate is avoided, the synthetic method is short in reaction time, easy to operate, low in cost, stable and high in efficiency, and the yield can be up to over 95%.

Description

technical field [0001] The invention relates to an organic synthesis method, in particular to a synthesis method for etherification of phenols. Background technique [0002] The etherifying agents used in the etherification of phenols are currently mainly three types of substances such as dimethyl sulfate, strong alkylating agents, and dimethyl carbonate. Dimethyl sulfate is a better etherifying agent. The rate is high, and the etherification process is simple and easy to control, but dimethyl sulfate is a highly toxic substance, which can be seriously harmful in contact with the skin or inhalation, so its purchase is extremely inconvenient. At the same time, the sulfuric acid in the by-product is harmful to equipment corrosion. Serious, and difficult post-processing; and strong alkylation reagents, such as methyl iodide, although high in reactivity, but high toxicity, and high price; compared with the above methylation reagents, dimethyl carbonate is less toxic and can be b...

AI Technical Summary

Problems solved by technology

[0002] The etherifying agents used in the etherification of phenols are currently mainly three types of substances such as dimethyl sulfate, strong alkylating agents, and dimethyl carbonate. Dimethyl sulfate is a better etherifying agent. The rate is high, and the etherification process is simple and easy to control, but dimethyl sulfate is a highly toxic substance, which can be seriously harmful in contact with the skin or inhalation, so its purchase is extremely inconvenient. At the same time, the sulfuric acid in the by-product is harmful to equipment corrosion. Serious, and difficult post-processing; and strong alkylation reagents, such as methyl iodide, although high in reactivity, but high toxicity, and high price; compared with the above methylation reagents, dimethyl carbonate is less toxic and can be biologically Degradation is an ideal substitute for dimethyl sulfate and methyl iodide, but since the methylation reaction temperature of dimethyl carbonate is 150°C, and its boiling point is only 90°C, it is difficult to carry out the methylation reaction under normal pressure

[0003] In the reaction of utilizing dimethyl carbonate and phenols to synthesize ethers at present, mainly include: 1) use phase-transfer catalyst to carry out under liquid phase or gas phase conditions, although reaction conditions are mild, there is product and catalyst separation difficulty, yield is low 2) adopting high temperature and high pressure, this method not only requires high reaction equipment, but also has a low yield; 3) microwave method, although the yield is high, but because it uses a single wave source, before carrying out the microwave reaction , it needs to be heated to the required reaction temperature first, which increases the reaction time and operation difficulty