3,4,5-Трифторфенилборная кислота

Описание

3,4,5-Trifluorophenylboronic acid is an arylboronic acid compound used in organic synthesis and as a reaction reagent. It can be used as a catalyst to catalyse the direct amidation of amino acid derivatives and the direct polycondensation of carboxylic acids and amines; it can also be used in the formation of new 1:1 co-crystals with urea C6H4BF3O2-CH4N2O components.

Химические свойства

Tan powder

Использование

Intermediates of Liquid Crystals

Синтез

Add 42mmol (10.08g) of magnesium chips into a 1000mL four-necked flask, add 2 pieces of iodine, and then add 200mL of anhydrous 2-methyltetrahydrofuran, heat the temperature to 50°C, and then slowly let it cool down to 40°C. And then drip 4-5mL of 3,4,5-trifluorobromobenzene 84.4g (0.4mol) and 50mL 2-methyltetrahydrofuran mixed solution, trigger the Grignard reaction, the temperature will rise rapidly after the reaction is initiated, use The temperature is lowered to 10-15°C in an ice-water bath, and a mixture (1) composed of 3,4,5-trifluorobromobenzene 84.4g (0.4mol) and 50mL 2-methyltetrahydrofuran (1), trimethyl borate is added dropwise. A mixture of 44 grams (0.42 mol) of ester and 50 mL of 2-methyltetrahydrofuran (2).The speed of the mixed solution (1) and the mixed solution (2) is kept the same, the dropping speed is controlled, and the dropping temperature is kept at 10-15°C . After the dropping is completed, the reaction is continued at room temperature for 8 hours.After the reaction is over, the reaction solution is slowly poured into dilute hydrochloric acid, and after the addition is complete, stir for 0.5-1.5h, separate the liquids, and then extract the aqueous phase twice, combine the organic phases, dry with anhydrous sodium sulfate, spin dry, and Recrystallization of ethyl chloride gave 3,4,5-Trifluorophenylboronic acid with a yield of 78% and a content of 99.6%.