阅读说明：本技术 光敏性联苯二胺单体的制备方法 (Preparation method of photosensitive biphenyldiamine monomer ) 是由 陈旭东 钟世龙 洪炜 于 2020-04-29 设计创作，主要内容包括：本发明公开了一种光敏性联苯二胺单体的制备方法,该制备方法包括以下步骤：(1)以4,4’-二羟基联苯为起始原料,于苯环2,2’、2,3’和3,3’中的任意一处位置引入硝基基团,制得化合物A；(2)在化合物A上的羟基位置引入末端为卤素的卤代直链烷基,制得化合物B；(3)在具有还原剂的反应环境下,将化合物B中的硝基还原成氨基,制得化合物C；(4)在具有路易斯碱的反应环境下,于化合物C上引入含有羟基的光敏性基团,以取代化合物C上卤代直链烷基末端的卤素基团,从而制得光敏性联苯二胺单体。本发明提供的光敏性联苯二胺单体的合成方法更简单安全、可控度更高、产率更可观,适用于对光敏性联苯二胺单体进行稳定连续大批量制备。(The invention discloses a preparation method of a photosensitive biphenyl diamine monomer, which comprises the following steps: (1) introducing a nitro group into any position of benzene rings 2,2 ', 2, 3' and 3,3 'by taking 4, 4' -dihydroxybiphenyl as a starting material to prepare a compound A; (2) introducing halogenated straight-chain alkyl with the tail end being halogen into the hydroxyl position on the compound A to prepare a compound B; (3) reducing the nitro in the compound B into amino under the reaction environment with a reducing agent to prepare a compound C; (4) under the reaction environment with Lewis base, a photosensitive group containing hydroxyl is introduced to the compound C to replace a halogen group at the tail end of halogenated straight-chain alkyl on the compound C, so that the photosensitive biphenyl diamine monomer is prepared. The synthesis method of the photosensitive biphenyldiamine monomer provided by the invention is simpler and safer, has higher controllability and considerable yield, and is suitable for stable, continuous and large-scale preparation of the photosensitive biphenyldiamine monomer.)

1. A preparation method of a photosensitive biphenyldiamine monomer is characterized by comprising the following steps: the preparation method comprises the following steps:

(1) introducing a nitro group into any position of benzene rings 2,2 ', 2, 3' and 3,3 'by taking 4, 4' -dihydroxybiphenyl as a starting material to prepare a compound A;

(2) introducing halogenated straight-chain alkyl with the tail end being halogen into the hydroxyl position on the compound A to prepare a compound B;

(3) reducing the nitro in the compound B into amino under the reaction environment with a reducing agent to prepare a compound C;

(4) under the reaction environment with Lewis base, a photosensitive group containing hydroxyl is introduced to the compound C to replace a halogen group at the tail end of halogenated straight-chain alkyl on the compound C, so that the photosensitive biphenyl diamine monomer is prepared.

2. The method for producing a photosensitive biphenyldiamine monomer according to claim 1, wherein: in the step (1): 4,4 ' -dihydroxybiphenyl is taken as a starting material, a nitro group is introduced into any one of 2,2 ', 2,3 ' and 3,3 ' on a benzene ring of the 4,4 ' -dihydroxybiphenyl through nitration reaction in a nitric acid solution at 5-10 ℃, and a nitrated product is washed, dried and recrystallized to obtain a compound A.

3. The method for producing a photosensitive biphenyldiamine monomer according to claim 1 or 2, wherein: in the step (2): dissolving the compound A prepared in the step (1) in a polar solvent, adding dihalogenated straight-chain alkane with the end containing halogen into the solution in a reaction environment with Lewis base, and reacting the halogen at one end of the dihalogenated straight-chain alkane with the hydroxyl on the compound A through nucleophilic substitution to generate ether bond to prepare the compound B.

4. The method for producing a photosensitive biphenyldiamine monomer according to claim 3, wherein: in the step (3): and (3) dissolving the compound B prepared in the step (2) in a polar solvent, adding a reducing agent at 0-5 ℃ to reduce the nitro group on the compound C into amino group, and preparing the compound C.

5. The method for producing a photosensitive biphenyldiamine monomer according to claim 4, wherein: in the step (4): and (3) dissolving the compound C prepared in the step (3) in a polar solvent, adding a photosensitive group containing hydroxyl into the solution in a reaction environment in which Lewis base exists, and reacting the hydroxyl in the photosensitive group with halogen in the compound C through nucleophilic substitution to generate an ether bond to obtain the photosensitive biphenyldiamine monomer.

6. The method for producing a photosensitive biphenyldiamine monomer according to any one of claims 2, 4, and 5, wherein: in the step (1), the mass fraction of the nitric acid solution is 50-80%.

7. The method for producing a photosensitive biphenyldiamine monomer according to claim 6, wherein: the polar solution used in the steps (2) to (4) is any one solution selected from methanol, tetrahydrofuran, chloroform, acetone, acetonitrile, N-dimethylformamide, N-dimethylacetamide and dimethylsulfoxide.

8. The method for producing a photosensitive biphenyldiamine monomer according to claim 7, wherein: the reducing agent in the step (3) is nickel chloride hexahydrate-sodium borohydride combination or stannic chloride-hydrochloric acid combination.

9. The method for producing a photosensitive biphenyldiamine monomer according to any one of claims 4 to 5 and 7 to 8, wherein: the Lewis base in the step (1) and the step (3) is selected from any one of lithium carbonate, potassium carbonate, sodium carbonate, rubidium carbonate, cesium carbonate, beryllium carbonate, magnesium carbonate, calcium carbonate, strontium carbonate and barium carbonate.

Technical Field

The invention belongs to the technical field of organic synthesis of compounds, and particularly relates to a preparation method of a photosensitive biphenyldiamine monomer.

Background

The polyimide has outstanding heat resistance and product dimensional stability, and has excellent mechanical property, dielectric property and insulating property. In addition, the polyimide has a very low coefficient of thermal expansion (12 to 20ppm, 1ppm = 10)^-6K^-1) The thermal expansion coefficient of the polyimide is similar to that of a metal copper wire (about 17.7 ppm), so that the polyimide has great application prospect in the field of flexible printed circuit boards. Polyimide is often used as a substrate or a protective layer in a flexible printed circuit board, and the conventional polyimide flexible circuit board preparation usually adopts a photoresist lithography technology and a nanoimprint technology, but the further development of the technology is limited by the complicated process, the low utilization rate of metal materials, the high pollution and the high equipment cost.

In order to solve the above problems, a method of grafting photosensitive molecules on a flexible circuit board substrate has been proposed and implemented, for example, an ink containing a metal precursor is jet-printed or grafted on the surface of the substrate, and a conductive metal is deposited on a previously patterned functional region by chemical deposition to prepare a flexible circuit board with a fine pattern. However, such methods have the disadvantages of limited graft polymer types, high cost and time consumption, and great difficulty in industrialization.

After continuous experimental research, polyimide with photosensitivity is generally used as a substrate and a protective layer of a flexible printed circuit board so as to reduce the preparation cost and the industrialization difficulty of the polyimide flexible printed circuit board. The photosensitive polyimide is prepared by performing condensation polymerization on a photosensitive biphenyl diamine monomer and acid anhydride, and performing imidization on the condensation polymerization. However, the prior art has low preparation efficiency of the photosensitive biphenyldiamine monomer, and the prepared photosensitive biphenyldiamine monomer has poor thermal stability, so that the photosensitive biphenyldiamine monomer cannot be stably and continuously prepared in a large scale.

Disclosure of Invention

In order to solve the above defects in the prior art, the invention aims to provide a preparation method of a photosensitive biphenyldiamine monomer, so that the synthesis method of the photosensitive biphenyldiamine monomer is simpler and safer, has higher controllability and more appreciable yield, and improves the thermal stability of the photosensitive biphenyldiamine monomer, thereby achieving the purpose of stably, continuously and massively preparing the photosensitive biphenyldiamine monomer.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a preparation method of a photosensitive biphenyldiamine monomer comprises the following steps:

(1) introducing a nitro group into any position of benzene rings 2,2 ', 2, 3' and 3,3 'by taking 4, 4' -dihydroxybiphenyl as a starting material to prepare a compound A;

(2) introducing halogenated straight-chain alkyl with the tail end being halogen into the hydroxyl position on the compound A to prepare a compound B;

(3) reducing the nitro in the compound B into amino under the reaction environment with a reducing agent to prepare a compound C;

(4) under the reaction environment with Lewis base, a photosensitive group containing hydroxyl is introduced to the compound C to replace a halogen group at the tail end of halogenated straight-chain alkyl on the compound C, so that the photosensitive biphenyl diamine monomer is prepared.

As a limitation of the present invention, in the step (1): 4,4 ' -dihydroxybiphenyl is taken as a starting material, a nitro group is introduced into any one of benzene ring 2,2 ', 2,3 ' and 3,3 ' on the 4,4 ' -dihydroxybiphenyl through nitration reaction in a nitric acid solution at 5-10 ℃, and a nitrated product is washed, dried and recrystallized to obtain a compound A.

As a limitation of the present invention, in the step (2): dissolving the compound A prepared in the step (1) in a polar solvent, adding dihalogenated straight-chain alkane with the end containing halogen into the solution in a reaction environment with Lewis base, and reacting the halogen at one end of the dihalogenated straight-chain alkane with the hydroxyl on the compound A through nucleophilic substitution to generate ether bond to prepare the compound B.

As a further limitation of the present invention, in the step (3): and (3) dissolving the compound B prepared in the step (2) in a polar solvent, adding a reducing agent at 0-5 ℃ to reduce the nitro group on the compound C into amino group, and preparing the compound C.

As still further limitation of the present invention, in the step (4): and (3) dissolving the compound C prepared in the step (3) in a polar solvent, adding a photosensitive group containing hydroxyl into the solution in a reaction environment in which Lewis base exists, and reacting the hydroxyl in the photosensitive group with halogen in the compound C through nucleophilic substitution to generate an ether bond to obtain the photosensitive biphenyldiamine monomer.

In the further limitation of the invention, in the step (1), the mass fraction of the nitric acid solution is 50-80%.

As still further limitation of the present invention, the polar solution in the steps (2) to (4) is selected from any one of methanol, tetrahydrofuran, chloroform, acetone, acetonitrile, N-dimethylformamide, N-dimethylacetamide, and dimethylsulfoxide.

As a further limitation of the present invention, the reducing agent in step (3) is a nickel chloride hexahydrate-sodium borohydride combination or a tin chloride-hydrochloric acid combination;

in another embodiment of the present invention, the lewis base in step (1) and step (3) is selected from any one of lithium carbonate, potassium carbonate, sodium carbonate, rubidium carbonate, cesium carbonate, beryllium carbonate, magnesium carbonate, calcium carbonate, strontium carbonate, and barium carbonate.

Due to the adoption of the technical scheme, compared with the prior art, the invention has the following beneficial effects:

the method for synthesizing the photosensitive biphenyldiamine monomer firstly nitrifies 4, 4' -dihydroxybiphenyl and then introduces halogenated alkyl chains at the hydroxyl positions, so that the halogenated alkyl chains are prevented from being damaged in the nitrifying process, and the yield of intermediate products is improved. And in the reduction process, the iron powder is replaced by a milder nickel chloride hexahydrate-sodium borohydride reduction combination or a stannic chloride-hydrochloric acid reduction combination to be used as a reducing agent, so that the requirement on the stirring power of a stirring device is reduced, the abrasion of the reducing agent on the inner wall of equipment during stirring is avoided, and the influence on the equipment is reduced. The preparation method realizes the preparation of the aromatic photosensitive biphenyl diamine monomer with high efficiency, stability and continuity, and effectively solves the problem that large-volume photosensitive groups are difficult to introduce into the benzene ring structure of the aromatic diamine monomer.

In conclusion, the synthesis method disclosed by the invention is simple, safe, high in controllability and easy for industrial production.

The method is used for stably and continuously preparing the photosensitive biphenyldiamine monomer in large batch.

Drawings

The invention is described in further detail below with reference to the figures and the embodiments.

FIG. 1 is a nuclear magnetic hydrogen spectrum of a photosensitive biphenyldiamine monomer in example 3;

FIG. 2 is a thermogravimetric plot of the photosensitive biphenyldiamine monomer of example 3;

FIG. 3 is a graph showing the UV absorption contrast spectra of the photosensitive small molecule containing hydroxyl group in example 3.

Detailed Description

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the description of the preferred embodiment is only for purposes of illustration and understanding, and is not intended to limit the invention.