Diisopropyl Ether → 1,2-Dichloro-3-(trifluoromethyl)-5-[1-(trifluoromethyl)ethenyl]benzene

Participants

Reaction Conditions

Reaction Steps

In a nitrogen atmosphere, to a solution of 26.2 g of 5-bromo-2,3-dichlorobenzotrifluoride and 9.1 g of diisopropyl ether in 250 mL of hexane, 57.5 mL of an n-butyl lithium hexane solution (1.55 M) was gradually dropped while stirring the solution at −10° C. After the completion of the dropping, the resultant mixture was stirred at the same temperature for 30 minutes. Next, into the reaction mixture, a solution of 9.26 g of trimethoxyborane in 30 mL of tetrahydrofuran was dropped and the resultant mixture was continuously stirred at room temperature further for 10 minutes. To this reaction mixture, 150 mL of water, 23.4 g of 2-bromo-3,3,3-trifluoropropene, 36.9 g of potassium carbonate and 0.131 g of 1,3-bis(2,6-diisopropylphenyl)imidazole-2-ylidene(1,4-naphthoquinone) palladium (0) dimer were added and the resultant mixture was stirred at 60° C. for 4 hours. After the completion of the reaction, the reaction mixture was left to be cooled down to room temperature, and 50 mL of ice water and 75 mL of ethyl acetate were added to the reaction mixture, followed by separating off the insoluble substance and by cleaning the insoluble substance with 75 mL of ethyl acetate. The organic phase of the filtrate was separated off and the resultant organic phase was washed with water and then dehydrated and dried over saturated saline and anhydrous sodium sulfate in this order. The solvent was distilled off under reduced pressure. The resultant residue was purified by silica gel column chromatography eluting with hexane to obtain 21.8 g of the objective substance as a colorless oily substance.

Provenance & Evidence