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ChemicalBook CAS DataBase List 2,3,4,5-Tetrafluorobenzyl alcohol
53072-18-7

2,3,4,5-Tetrafluorobenzyl alcohol synthesis

4synthesis methods
-

Yield: 97%

Reaction Conditions:

with sodium tetrahydroborate in 1,2-dimethoxyethane;water at 5 - 80; for 4 h;Inert atmosphere;

Steps:

2
To a 500 mL four-necked flask, 4.16 g (0.11 mol) of NaBH4 and 10 g of ethylene glycol dimethyl ether were added, and the mixture was heated to 78 to 80 ° C with stirring under nitrogen atmosphere, and refluxed for 3 hours. After the completion of the activation reaction, the temperature was lowered to 20 to 30 ° C, 300 g of water was added, and the mixture was stirred and dissolved, and the temperature was lowered to 5 ° C, and 54.1 g of 2,3,4,5-tetrafluorobenzoyl chloride was added dropwise under nitrogen atmosphere. The reaction is strongly exothermic, and gas and solids are formed, and the reaction temperature is controlled at 5 to 15 ° C for about 3 hours. The addition was completed at this temperature for 1 hour. Add 100 g of dichloromethane and stir for 10 minutes, filter out the insoluble inorganic salt, rinse the filter cake with 50 g of dichloromethane, combine the filtrate, separate the organic layer, and distill off the dichloromethane to obtain the white solid product 2, 3, 4 , 5-tetrafluorobenzyl alcohol 44.5 g, yield 97%. The combined yield in two steps was 96.03%

References:

Dalian Qikai Pharmaceutical Technology Co., Ltd.;Yuan Feng;Jiang Dianping;Zhang Hongxue;Sun Liqin CN109293478, 2019, A Location in patent:Paragraph 0047; 0049-0051

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