Yield:2379-17-1 40 g

Reaction Conditions:

with hydrogen fluoride at 100; under 2812.19 Torr; for 17 h;Autoclave;Inert atmosphere;Temperature;

Steps:

2

In a 500 mL three-necked flask equipped with a water separator,110 g (0.5 mol) of hexafluoroacetone trihydrate was added,O-xylene 106g (1mol), layered, stirring, the reaction solution for the milky white mixture,Heated to the reflux temperature, water separator in the water separation (water separator by adding about 45g o-xylene), continue to heat reflux to the basic anhydrous separation, the reaction bottle liquid colorless and transparent,Is a mixture of ortho-xylene and hexafluoroacetone monohydrate; the mixture of ortho-xylene and hexafluoroacetone monohydrate was transferred to 1 L of a vacuum autoclave, 55 g of anhydrous hydrogen fluoride was added,Heating to 100 , the reaction of about 17h, the reaction pressure of about 3.7atm, after the end of the reaction, cooling,The organic layer was separated and the aqueous layer was extracted with 3 x 50 mL of ethyl acetate to separate the organic phase, and the organic layer was separated from the organic layer. The organic layer was extracted with 3 x 50 mL of ethyl acetate,Washed with sodium bicarbonate solution to neutral, and then washed with water, saturated brine, dried over anhydrous sodium sulfate, filtered, and the filtrate was distilled to remove the low boiling solvent to obtain 75 g of brown liquid,The main product is 2- (3,4-dimethylphenyl) -1,1,1,3,3,3-hexafluoro-2-propanol.The gas chromatography showed a content of 89.7%, and after distillation under reduced pressure, 40 g of 2- (3,4-dimethylphenyl) -1,1,1,3,3,3-hexafluoro-2-propanol was obtained.2- (3,4-dimethylphenyl) -1,1,1,3,3,3-hexafluoro-2-propanol selectivity of 97.6%.

References:

CN106699509,2017,A Location in patent:Paragraph 0022-0023