- Preparation method of pentaerythritol triallyl ether
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The invention provides a pentaerythritol triallyl ether preparation method, and the method comprises: S1, adding pentaerythritol monoallyl ether and sodium hydroxide into a reaction kettle, heating, carrying out a degassing and dehydration reaction for 3-7 h, slowly adding allyl chloride into the reaction kettle, and carrying out a thermal insulation reaction for 3-6 h; S2, performing cooling to below 35 DEG C, adding water into sodium chloride with the same amount of substance as sodium hydroxide in S1 to prepare a sodium chloride saturated solution, standing for layering, discharging a lower-layer aqueous solution, and reserving an upper-layer semi-finished product pentaerythritol diallyl ether; S3, adding sodium hydroxide into the semi-finished product, and repeating the steps S1 and S2to obtain a pentaerythritol triallyl ether crude product. According to the process, a phase transfer catalyst is not needed, so that the cost is saved; compared with the existing process, the feedingof sodium hydroxide and allyl chloride is greatly reduced, and one hydroxyl group is averagely excessive by 2.5% in the reaction; feeding is reduced, by-products are reduced, rectification is not needed, direct post-treatment can be achieved, and cost is further saved.
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Paragraph 0013; 0024-0032
(2021/03/13)
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- Preparation method of pentaerythritol triallyl ether
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The invention provides a preparation method of pentaerythritol triallyl ether and particularly relates to the technical field of synthesis of pentaerythritol triallyl ether. The method is characterized by comprising the following steps: S1, under normal pressure, feeding pentaerythritol, pentaerythritol triallyl ether, tetrabutylammonium bromide and 50% sodium hydroxide aqueous solution into a stirring reaction kettle, and heating the mixture to dissolve pentaerythritol into liquid; S2, dropwise adding chloropropene, keeping chloropropene and water evaporated, and layering the chloropropene and water after condensation, and returning chloropropene to the stirring reaction kettle; and S3, after the reaction is finished, adding water, and cooling and standing the mixture for layering, and carrying out reduced pressure distillation on the upper organic phase to obtain the product pentaerythritol triallyl ether. According to the preparation method of pentaerythritol triallyl ether providedby the invention, pentaerythritol triallyl ether is adopted as a solvent during synthesis, the addition of an inert solvent in the existing process is optimized and removed, rectification recycling or environment-friendly treatment measures of the inert solvent are not needed, and high-pressure operation of taking water as the solvent is avoided, so that the reaction is beneficial to the generation of pentaerythritol triallyl ether.
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Paragraph 0053-0063
(2020/06/16)
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- Total synthesis of high loading capacity PEG-based supports: Evaluation and improvement of the process by use of ultrafiltration and PEG as a solvent
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The present work deals with the total synthesis of high loading capacity PEG supports with attention focused on improving the greenness of all the steps. The systematic calculation of green metrics offers an opportunity to evaluate the greenness and then to improve the process. To evidence such an improvement, the evaluation of the optimized processes was compared with that of the classical ones.
- Turgis, Raphael,Billault, Isabelle,Acherar, Samir,Auge, Jacques,Scherrmann, Marie-Christine
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p. 1016 - 1029
(2013/07/25)
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- Diphilic carbosilane dendrimers with different densities of the hydrophilic layer
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A universal method for the synthesis of hydrophilic dendrimers was considered. The method is based on a combination of carbosilane dendrimers with different molecular organizations and hydrophilizing agents, viz., substituted hydride silanes containing one and three protected hydroxyl groups. The combination of a limited set of the mentioned reagents makes it possible to control the ratio of hydrophilic and hydrophobic moieties of the molecular structure in wide limits. A simple and convenient method for the removal of trimethylsilyl protection of hydroxyl groups in the surface layer of dendrimers was developed.
- Getmanova,Tereshchenko,Ignat'eva,Tatarinova,Myakushev,Muzafarov
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p. 137 - 143
(2007/10/03)
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