Tetramethylbiphenyl preparation method

A technology of tetramethylbiphenyl and halogenated o-xylene, which is applied in the field of preparation of biphenyl compounds, can solve problems such as difficulty in large-scale production and stringent requirements for instruments, so as to facilitate recycling, reduce equipment requirements, and simplify follow-up Effect of treatment

Inactive Publication Date: 2010-02-03
BYD CO LTD
View PDF1 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] In order to overcome the disadvantages of harsh reaction conditions and instrument requirements for the production of tetramethylbiphenyl in the prior art, and the disadvantages that it is difficult to realize large-scale production, the present invention provides a m

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Tetramethylbiphenyl preparation method
  • Tetramethylbiphenyl preparation method
  • Tetramethylbiphenyl preparation method

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0016] A preparation method of tetramethylbiphenyl, comprising the coupling reaction of halogenated aromatic hydrocarbons and the extraction of products, the reactants of the coupling reaction include using alcohol as a reducing agent, using palladium carbon as a catalyst, and using an alkaline aqueous solution as a solvent.

[0017] Wherein, the reactant halogenated arene is preferably halogenated o-xylene, which can be a compound shown in formula (II), wherein X is a halogen atom, preferably Br, Cl atom, and the halogen atom is on the benzene ring The substitution position of can be 4 or 3. The halogenated o-xylene is selected from one of 3-halogenated o-xylene or 4-halogenated o-xylene, or a mixture of the two isomers.

[0018]

[0019] Wherein, alcohol plays the role of reducing agent, can be various alcohols known to those skilled in the art, comprise monohydric alcohol; Polyhydric alcohols such as dibasic alcohol, tribasic alcohol, the present invention is preferably...

example 1

[0035] Add 120ml of distilled water, 6g of palladium carbon (70% water content, 3% palladium content in the palladium carbon), 46.67gKOH (5 / 6mol) and 30.83 g (1 / 6 mol) of bromo-o-xylene (4-bromo-o-xylene). Weigh 18.4g of glycerol (0.2mol) and dissolve it in 30ml of aqueous solution, and transfer it to a constant pressure funnel. The reaction flask was purged of air with nitrogen and sealed tightly. The temperature of the water bath was raised to 99°C, and the glycerin solution was added dropwise, and the dropping speed was controlled, and the dropping time was 1.8 hours. After the dropwise addition, keep the reaction at 99°C for 12h. Cool, filter with suction, transfer the filtrate to a separatory funnel and let stand to separate layers to obtain an organic liquid. The aqueous phase was extracted with ether and combined into the organic liquid, and the organic liquid was distilled off under reduced pressure to obtain a light yellow solid. Recrystallized with a small amount...

example 2

[0037] Add 180ml of distilled water, 7.6g of palladium carbon (70% water content, 3% palladium content in palladium carbon), 56gKOH (1mol) and 46.25 g (0.25mol) a bromo-o-xylene (containing 4-bromo-o-xylene and a small amount of 3-bromo-o-xylene). Weigh 29.4g of glycerol (0.32mol) and dissolve it in 50ml of aqueous solution, and transfer it to a constant pressure funnel. The reaction flask was purged of air with nitrogen and sealed tightly. The temperature of the oil bath was raised to 100°C, and the glycerin solution was added dropwise, and the dropping rate was controlled, and the dropping time was 1.5 hours. After the dropwise addition, the reaction was maintained at 100°C for 13h. Cool, filter with suction, transfer the filtrate to a separatory funnel and let it stand, and separate to obtain an organic liquid. The aqueous phase was extracted with ether, and combined into the organic liquid, the ether was removed by heating under reduced pressure, and the organic liquid ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a tetramethylbiphenyl preparation method which comprises the coupling reaction of halogenated aromatic hydrocarbon and the extraction of the product, wherein the reactants of the coupling reaction comprises alcohol used as reducing agent, palladium carbon used as catalyst and alkaline water solution used as solvent. The invention also comprises the recrystallization by usingmethanol so as to prepare high purity tetramethylbiphenyl. The invention provides the simple and economic preparation method of tetramethylbiphenyl industrialized production with low demands for thedevice and technology and the prepared tetramethylbiphenyl has higher purity and meets the demands of the raw material used to prepare high performance polyimide.

Description

【Technical field】 [0001] The invention relates to a preparation method of biphenyl compounds, in particular to a preparation method of tetramethylbiphenyl. 【Background technique】 [0002] Polyimide has excellent heat resistance, dielectric properties, and mechanical properties, and is widely used in aerospace and electronics fields. The polyimide synthesized from biphenyltetracarboxylic dianhydride and p-phenylenediamine has a thermal decomposition temperature of 600°C, and is one of the most thermally stable polymers. The polyimide polymerized by biphenyltetracarboxylic dianhydride has a small thermal expansion coefficient, which is basically equivalent to copper foil, and has good dielectric properties. It is mainly used for electronic and electronic products with high safety and reliability, such as flexible circuit boards. aerospace field. Therefore, as an important monomer of high-performance polyimide, biphenyltetracarboxylic dianhydride has received extensive attent...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C07C15/14C07C1/26
Inventor 赖学平崔玮乾隆彭卫国
Owner BYD CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap