CN105669483A

CN105669483A - Preparation method of propyzamide

Info

Publication number: CN105669483A
Application number: CN201610113757.0A
Authority: CN
Inventors: 缪宗德
Original assignee: Binhai New Oriental Medical Chemical Co Ltd
Current assignee: Binhai New Oriental Medical Chemical Co Ltd
Priority date: 2016-03-01
Filing date: 2016-03-01
Publication date: 2016-06-15
Anticipated expiration: 2036-03-01
Also published as: CN105669483B

Abstract

The invention relates to an organic synthesis method and in particular relates to a preparation method of propyzamide. According to the method provided by the invention, 3,5-dichlorobenzeneformonitrile is used as a raw material, and is subjected to alcoholysis reaction with 3-methyl-3-hydroxybutyne under a Lewis acid catalytic condition to synthesize the propyzamide in one step. With the adoption of the preparation method of the propyzamide, a process path is simplified, reaction conditions are improved and the yield of a product is improved; the emission of three wastes is greatly reduced, and a green and feasible scheme is provided for industrial production.

Description

A kind of preparation method of pentyl xanthate

Technical field

The preparation method that the present invention relates to a kind of pentyl xanthate, belongs to the field of chemical synthesis.

Background technology

Pentyl xanthate, chemical name is 3,5-bis-chloro-N-(1,1-alkynyl dimethyl) Benzoylamide, is a kind of widely used herbicide, is usually used in the control of the weeds such as broad leaved weed. The synthetic method of the pentyl xanthate of report at present, mainly 3,5-dichlorobenzoic acids obtain 3,5-dichlorobenzoyl chlorides through acidylate, and 3,5-dichlorobenzoyl chlorides prepare with 3-methyl-3-aminobutyne condensation reaction again. Chloride process belongs to dangerous technique, and can produce a large amount of spent acid. Meanwhile, condensation reaction has again a large amount of abraum salt to generate. And 3, the preparation method of 5-dichlorobenzoic acid is more, and comparing one had superiority is CN103242190B 3, the 5-dichlorobenzonitrile Hydrolyze method proposed: 3,5-dichlorobenzonitrile is first hydrolyzed to 3 under alkaline environment, 5-dichlorobenzoic acid salt, then acidifying obtains 3,5-dichlorobenzoic acids under sour environment, or 3,5-dichlorobenzonitrile is directly hydrolyzed under sour environment, obtains 3,5-dichlorobenzoic acids. No matter which kind of method is hydrolyzed, and all produces a large amount of three wastes. 3-methyl-3-aminobutyne, mainly with 3-methyl-3-hydroxyl butine for raw material, through chlorination, ammonification two step prepares. This process not only yield is low, and uses a large amount of soda acid, and safety and environmental protection has bigger pressure. In sum, tradition prepares the technique of pentyl xanthate, and not only process flow is long, and yield is low, pollutes big, and production environment is poor. Therefore finding new preparation method for pentyl xanthate is problem demanding prompt solution.

Summary of the invention

The preparation method that it is an object of the invention to provide a kind of pentyl xanthate, the method is that pentyl xanthate preparation provides a kind of new thinking, and its process safety is easy, environmental friendliness, good quality of product, overcomes the shortcoming existed in prior art. Present invention employs following proposal: add oxolane or methyltetrahydrofuran in a reservoir, put into catalyst Lewis acid, then at-5～15 DEG C of temperature, drip 3,5-dichlorobenzonitriles and 3-methyl-3-hydroxyl butine. Dropping is finished, and keeps 15～35 DEG C, maintains 3～10 hours, is incubated alcoholysis. Insulation is finished, and cools to 0～10 DEG C and adds aqueous alkali tune pH value to neutral, terminates reaction. Then normal pressure or remove solvent under reduced pressure at temperature≤70 DEG C. Being eventually adding toluene or dimethylbenzene as recrystallization solvent, be warmed up to 60～70 DEG C, make material dissolution, stand, branch vibration layer, organic layer filter pressing removes insoluble matter, and cleaner liquid is cooled to 0～10 DEG C, centrifugal, obtains soaking wet product, then through dry, obtains pentyl xanthate finished product. Yield is more than 75%, and content is up to 99.0%. Reaction equation is as follows:

The invention have the characteristics that

1, simple process, equipment is simple.Traditional handicraft is with 3,5-dichlorobenzonitriles, and 3-methyl-3-hydroxyl butine is that the prepared pentyl xanthate of raw material at least needs five steps reactions. And the present invention only needs single step reaction, greatly reduce equipment investment. 2, yield is greatly improved. Traditional handicraft because operation is long, has often walked loss of material on the one hand; On the other hand, 3-methyl-3-hydroxyl butine and derivant physical property thereof are relatively active, cause the yield relatively low (in 3-methyl-3-hydroxyl butine less than 50%) of 3-methyl-3-hydroxyl butine, and therefore, total recovery is relatively low. And reaction condition of the present invention is gentle, target product is single, thus yield is higher. 3, not in use by chloride, chlorination, the dangerous technique such as ammonification, thus operating environment is improved. 4, pollutant emission is greatly decreased. Using a large amount of soda acid in former technique, produce corresponding spent acid alkali salt, integrated disposal processing is complicated, and processing cost is higher. And wastewater flow rate of the present invention is few, and biodegradability is high. To sum up knowing, the present invention not only simplifies processing route, reduces production cost, improves operating environment, and the discharge of pollutant is greatly reduced, and provides a feasible scheme of green for industrialized production. Detailed description of the invention is as follows: below in conjunction with instantiation, the present invention is made a detailed explanation. Example 1 adds oxolane 420g in 1000mL four-hole bottle, puts into zinc chloride 7.9g, then drips 3,5-dichlorobenzonitrile 200g and 3-methyl-3-hydroxyl butine 110g at-5～5 DEG C of temperature. Dropping is finished, and 20～25 DEG C are incubated 5 hours, so as to alcoholysis. Insulation is finished, and cools to 5 DEG C and adds aqueous sodium carbonate tune pH value to 7, terminates reaction. Then at 65～70 DEG C, solvent is evaporated off. Add toluene 300g, after dissolving, be cooled to 0～5 DEG C of recrystallization, centrifugal, obtain soaking wet product, then through dry, obtain pentyl xanthate finished product 249.2g, content is 99.1%, and yield is 83.7%. Example 2 adds methyltetrahydrofuran 500g in 1000mL four-hole bottle, puts into aluminum chloride 6.5g, then drips 3,5-dichlorobenzonitrile 200g and 3-methyl-3-hydroxyl butine 130g at 0～5 DEG C of temperature. Dropping is finished, and 20～25 DEG C are incubated 7 hours, so as to alcoholysis. Insulation is finished, and cools to 10 DEG C and adds sodium bicarbonate aqueous solution tune pH value to 7, terminates reaction. Then at 65～70 DEG C, solvent is evaporated off. Add dimethylbenzene 280g, after dissolving, be cooled to 0～10 DEG C of recrystallization, centrifugal, obtain soaking wet product, then through dry, obtain pentyl xanthate finished product 224.2g, content is 99.0%, and yield is 75.3%.

Claims

1. add solvent orange 2 A and Lewis acid, dropping 3,5-dichlorobenzonitriles and 3-methyl-3-hydroxyl butine in a reservoir, be incubated alcoholysis.

2. insulation is finished, and adds aqueous alkali and adjusts pH value to neutral, terminates reaction.

3. then through precipitation, recrystallization, dry, obtain pentyl xanthate finished product.

4. the preparation method of pentyl xanthate as claimed in claim 1, it is characterised in that described solvent orange 2 A is oxolane or methyltetrahydrofuran.

5. the preparation method of pentyl xanthate as claimed in claim 1, it is characterised in that described Lewis acid be zinc chloride, aluminum chloride, ferric chloride, zinc bromide, alchlor, ferric bromide, phosphoric acid, sulphuric acid therein one or more.

6. the preparation method of pentyl xanthate as claimed in claim 1, it is characterised in that described aqueous alkali is the aqueous solution of sodium hydroxide, sodium carbonate, sodium bicarbonate one of which.

7. the preparation method of pentyl xanthate as claimed in claim 1, it is characterised in that described material 3,5-dichlorobenzonitrile: 3-methyl-3-hydroxyl butine: Lewis acid: solvent orange 2 A mol ratio is 1:1.05～1.5:0.01～0.2:3～20.

8. the preparation method of pentyl xanthate as claimed in claim 1, it is characterised in that described dropping temperature is-5～15 DEG C, insulation glycolysis temperature is 15～35 DEG C, and temperature retention time is 3～10 hours, and adding aqueous alkali final temperature is 0～10 DEG C, precipitation temperature≤70 DEG C.

9. the preparation method of pentyl xanthate as claimed in claim 1, it is characterised in that described recrystallization refers to procedure below: be solvent with toluene or dimethylbenzene, it is warmed up to 60～70 DEG C, branch vibration layer, then filter pressing, cleaner liquid is as cold as 0～10 DEG C, is centrifuged to obtain soaking wet product.