Preparation method of 4, 6-dichloropyrimidine

A technology of dichloropyrimidine and dihydroxypyrimidine, which is applied in the field of preparation of pesticide raw materials, can solve problems such as high technical requirements, large amount of three wastes, and high risk of phosgene, and achieve mature and reliable process technology, reduce risks, and be environmentally friendly Effect

CN102936224AInactive Publication Date: 2013-02-20LIANYUNGANG GUOSHENG CHEM
3 Cites 5 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2013-02-20
Estimated Expiration
Not applicable · inactive patent

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
Patent Text Reader

Abstract

The invention provides a preparation method of 4, 6-dichloropyrimidine. The preparation method comprises the following steps: feeding formamide, absolute ethyl alcohol and sodium ethoxide into a container; stirring and heating; dropping diethyl malonate; reflowing and maintaining the temperature after the dropping; recovering the absolute ethyl alcohol and water-containing ethyl alcohol; dropping hydrochloric aqueous solution until the pH (Potential of Hydrogen) of the reaction liquid is 2 to 6; cooling; centrifuging and drying to obtain 4, 6-dihydroxypyrimidine; feeding the 4, 6-dihydroxypyrimidine, dichloroethane and a chlorination catalyst into the container; stirring and slowly heating until reaching reflowing; dropping thionyl chloride; maintaining the temperature after the dropping; then cooling; recovering the dichloroethane; collecting the dichloroethane and finished product; cooling the finished product in a crystallizing kettle; and centrifuging and drying to obtain the finished product of 4, 6-dichloropyrimidine. The preparation method can reduce the risk, is more reasonable in technology, simple and convenient, low in cost, high in quality, environmentally friendly, and more specifically suitable for industrial production, and can reach over 83% of the total reaction yield based on diethyl malonate; and the quality of the 4, 6-dichloropyrimidine meets international standard.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention relates to a method for preparing pesticide raw materials, in particular to a method for preparing 4,6-dichloropyrimidine. Background technique

[0002] 4,6-dichloropyrimidine is the raw material for the synthesis of azoxystrobin. The chemical name of azoxystrobin is (E)2-[2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]benzene Base]-3-methyl methoxyacrylate, this product is a methoxyacrylate (Strobilurin) fungicide, highly efficient, broad-spectrum, for almost all fungal kingdoms (Ascomycotina, Basidiomycotina, Flagella Mycotina and Deuteromycotina) diseases such as powdery mildew, rust, glume blight, net spot, downy mildew, rice blast, etc. have good activity. It can be used for stem and leaf spray, seed treatment, and soil treatment. It is mainly used for grain, rice, peanut, grape, potato, fruit tree, vegetable, coffee, lawn, etc.

[0003] Currently reported synthetic methods, due to consideration of the yield and manufacturing costs, the cy...

Examples

Embodiment 1

Embodiment 2

Embodiment 3