A method for efficiently preparing high-quality benzodifuranone

Abstract

The invention discloses a method for efficiently preparing high-quality benzodifuranone, belonging to the field of optimization of post-treatment routes of organic synthesis. The method comprises thefollowing specific steps: (1) putting N,N-diethyl-furan-3-formamide into anhydrous THF, dropwise adding a hexane solution of n-BuLi at 4 DEG C to -10 DEG C in a protective atmosphere, and after the addition is finished, raising the temperature to room temperature and performing stirring for 4.0 h to 6.0 h; (2) pouring a mixed solution obtained in the previous step into deionized water, and performing stirring for 2.0-5.0 hours at room temperature; (3) removing deionized water and THF by rotating through a rotary evaporator; (4) pouring a residual viscous material into a sand core funnel provided with a separation layer, and performing washing with dichloromethane multiple times until the color of a filtrate becomes transparent; (5) removing dichloromethane in the filtrate in the manner ofrotating through the rotary evaporator; and (6) carrying out drying in vacuum to obtain the high-quality benzodifuranone.

Description

technical field [0001] The invention belongs to the category of organic synthesis and process route optimization, and specifically relates to a method for efficiently preparing high-quality benzodiofuranone. Background technique [0002] Benzo[1,2-b:4,5-b']difuran (BDF) has a regular structure and a high conjugated skeleton. At the same time, due to the strong electronegativity of the oxygen atoms in furan, BDF-based polymers Exhibits a higher highest occupied molecular orbital (HOMO) energy level. In addition, due to the wide range of sources of furan, the initial raw material for BDF synthesis, BDF units show great value in the synthesis of low-cost polymer materials. However, the low yield and poor quality of benzodifuranone, a key intermediate in the synthesis of BDF, limit the application and promotion of BDF in the preparation of low-cost polymer materials. [0003] The synthesis and purification process route of benzodifuranone reported in the literature is as attac...

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Problems solved by technology

[0005] There are several disadvantages in the above reaction method: 1) The reaction process uses flammable and explosive ether solvent; 2) The organic base used in the reaction is LDA, which needs to be prepared and used at low temperature, which is relatively complicated; 3) The crude product is heavy in glacial acetic acid. Crystallization, glacial acetic acid is difficult to remove; 4) After the reaction, the organic solvent cannot be recycled; 5) The reaction yield is low

Compared with the first reported process route, the newly improved process route simplifies the purification process of the target product, but there are still several disadvantages: 1) The post-reaction treatment period is too long; 2) The product purity is low; 3) The reaction yield is relatively low. Low( Journal of Polymer Science Part A: Polymer Chemistry , 2012, 50 , 4316)

Compared with the second reported process route, the newly improved process route has improved the yield, but it also has several disadvantages: 1) The post-reaction treatment period is too long; 2) The product purity is still not high; 3) The post-reaction treatment organic solvent cannot Recycling; 4) The reaction yield is low ( Journal of Materials Chemistry , 2012, 22 , 17724)

[0008] At present, the preparation and post-treatment process routes of benzodifuranone are all based on the above three methods, but the reaction cycle involved is long, the product purity is not high, the reaction yield is low, and the post-treatment organic solvent cannot be recycled, which greatly restricts Large-scale preparation and popularization of benzodiofuranone

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