1,3-Bis(2,6-diisopropylphenyl)imidazolium chloride → HCID 57917724, compound

Participants

Reaction Conditions

Reaction Steps

3-Methyl-piperazine-1,3-dicarboxylic acid 1-tert-butyl ester (120 mg, 0.49 mmol) and 2-Bromo-5-trifluoromethyl-pyridine (133 mg, 0.59 mmol) were dissolved in 2.0 mL of anhydrous toluene (degassed). In a separate, septum-equipped vial were placed tri(dibenzylideneacetone)dipalladium(0) (22 mg, 0.024 mmol), 1,3-bis(2,6-di-i-propylphenyl)imidazolium chloride (42 mg, 0.1 mmol) and sodium t-butoxide (57 mg, 0.59 mmol). This “catalytic” vial was equipped with a magnetic stir bar and flushed with dry nitrogen. The reactant solution was next transferred to the “catalytic” vial and the mixture was stirred at 100° C. for 5 h. After this period the mixture was combined with 20 mL of hexane/EtOAc (2:1) and was passed through a pad of Celite. The resulting filtrate was evaporated in vacuo and purified using flash silica chromatography (0-20% EtOAc/Hexane) to yield 110 mg (58%) of 4-(5-Trifluoromethyl-pyridin-2-yl)-piperazine-1,3-dicarboxylic acid 1-tert-butyl ester 3-methyl ester.

Provenance & Evidence