Simple and convenient method for producing high-purity ortho-formate

Abstract

The invention provides a simple and convenient method for producing high-purity ortho-formate by using acrylonitrile byproduct hydrocyanic acid. The method comprises the following steps: firstly producing amine salt from the acrylonitrile byproduct hydrocyanic acid, fatty alcohol and hydrogen chloride, subsequently performing alcoholysis reaction on the presence of corresponding fatty alcohol so as to obtain an ortho-formate reaction liquid, adding a proper amount of an alkali substance in the generated ortho-formate reaction liquid, decomposing nitrogenous impurity compounds such as byproduct 1,3,5-s-triazine at certain temperature, wherein the decomposed product is nitrogen and solid formate with low boiling point, performing aftertreatment on the reaction liquid so as to obtain the high-purity ortho-formate through normal distillation. Therefore, the purpose of producing the high-purity ortho-formate with high yield is achieved.

Description

Technical field: [0001] The invention relates to the field of organic synthesis, in particular to a convenient method for producing high-purity orthoformate by using hydrocyanic acid as a by-product of acrylonitrile. The method decomposes impurities in the presence of alkaline substances to achieve the production of high-purity raw Purpose of formate. Background technique: [0002] Orthoformate is an important intermediate in organic synthesis, used as a pharmaceutical intermediate, as well as an intermediate in pesticides, chemicals, and spices, and used in the synthesis of vitamin A, vitamin B1, sulfonamides, and antibiotics. In addition, orthoformate is also widely used in coatings for the dehydration of polyurethane or epoxy coatings to prevent hardening. The market demand is gradually increasing. [0003] The production methods of orthoformate mainly include: hydrocyanic acid method, propylene oxide method, methylamine method and metal sodium or sodium methoxide metho...

AI Technical Summary

Problems solved by technology

These impurities, such as 1,3,5-s-triazine and other nitrogen-containing impurities can not only produce unpleasant odors, but also affect the application of orthoformate, such as in trimethyl orthoformate, if 1,3,5 - the content of nitrogen-containing impurity compounds such as s-triazine exceeds 0.2%, in the production of 1,1,3,3-tetramethoxypropane, the yield of reaction will be greatly reduced, thereby limiting the production of trimethyl orthoformate application

[0004] The method of separating trimethyl orthoformate and these impurities has been mentioned in some documents, such as USP3258496, USP3121751, Chinese invention patent application CN00111314.3, CN03129005.1, CN200310112977.4, CN200410016459.7, CN2011103847763.7, CN201283102 .6 and so on, wherein the methods adopted are: 1. during the alcoholysis reaction, use hydrogen chloride to keep the reaction at about pH3; 2. add nickel chloride, aluminum chloride, ferric chloride, chloride Zinc and other Lewis acids, heat to decompose impurities; ③The crude orthoformate is fed with hydrogen chloride gas to generate 1,3,5-s-triazine hydrochloride solids, which are removed by filtration; ④Use acidic resin to absorb impurities; ⑤Add Heavy metal salt ZnCl 2 , CuCl 2 、CoCl 2 etc. to purify but the above-mentioned method all can not obtain the orthoformate of high purity with higher yield (more than 88%), the product that i.e. trimethyl orthoformate content more than 99%