Continuous synthesis method for methyl 3,3-dimethyl pentenoate

Abstract

The invention discloses a synthesis method for methyl-3,3-dimethyl-4-pentenoate. The method comprises the following steps of: A) continuously feeding trimethyl orthoacetate, a catalyst and 3-methyl-2-butenl-1-ol according to a molar ratio of 1:0.0005-0.02:0.1-0.5 into a tubular or kettle reactor, mixing and reacting for 5 to 60 minutes to produce methyl-3,3-dimethyl-4-pentenoate synthesis feed liquid at the temperature of between 0 and 40 DEG C; and B) continuously feeding the methyl-3,3-dimethyl-4-pentenoate synthesis feed liquid produced in the step A into a separating tower, removing methanol serving as a byproduct and excessive trimethyl orthoacetate, and rectifying tower bottom to obtain the methyl-3,3-dimethyl-4-pentenoate product. The synthesis method for the methyl-3,3-dimethyl-4-pentenoate in the invention has the advantages of high reaction speed, short period, a little of byproduct tar and simplicity and is particularly suitable for industrial large-scale production, and the reaction yield is stabilized at over 88 percent and product content is over 99.5 percent.

Description

technical field [0001] The invention relates to a method for synthesizing methyl pyridinate, in particular to a method for continuously synthesizing methyl carditinate. Background technique [0002] Methyl bentinate, the chemical name is 3,3 dimethyl-4-pentenoic acid methyl ester, the pure product is a colorless and transparent liquid with a special pungent smell, soluble in ethanol, ethyl acetate, ether and other organic solvents , insoluble in water; the structural formula is as follows: [0003] [0004] Methyl bentinate is an important chemical raw material. It is not only used in general organic synthesis, but also used as an intermediate in the synthesis of pyrethroid pesticides of fluorine, chlorine and bromine in the pesticide chemical industry. , occupies an important position, and was the first to be industrialized by the British Zeneca Company in the early 1970s. [0005] The literature "Research on the Synthesis of Methyl Cardyrinate" (Pesticide 1996, Issue ...

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Problems solved by technology

[0005] The literature "Research on the Synthesis of Methyl Cardyrinate" (Pesticide 1996, Issue 09) has carried out a literature review on the synthesis of Methyl Cardyrinate. In the prior art, the batch synthesis process is mainly used, which leads to long reaction time and long material time. Heated for a long time, there is a lot of tar in the rectification process, and the final product yield is only about 65-85%

[0006] Up to now, there is no continuous synthesis process report of methyl pyridinate