Trifluoroacetic acid → HCID 66643825, compound

Participants

Reaction Steps

(3-bromo-2,4-dimethylphenyl)methanol (2.0 g, 9.3 mmol), and thalium(III) trifluoroacetate (7.50 g, 14.0 mmol) were added to a 250 mL flask containing a stir bar. The flask was then placed in a cooling bath at 0° C. To the flask was added TFA (150 mL) slowly. The resulting mixture was then stirred at room temperature overnight. The TFA was removed under reduced pressure at 30° C. and the resulting residue was redissolved in dichloroethane and concentrated twice (2×100 mL). The residue was then pumped under high vacuum for 45 min. To the dried residue was then added palladium dichloride (165 mg, 0.930 mmol), lithium chloride (788 mg, 18.6 mmol), and magnesium chloride (750 mg, 18.6 mmol). The resulting mixture was dissolved in MeOH (160 mL). The mixture was then degassed and purged with CO (3 times). The flask under CO was stirred at room temp for 4 hours; the color of the reaction mixture changed from white to cream then to brownish. The color of the reaction then finally changed from brownish to black up on which time the reaction had gone to completion as evidenced by LC as well as TLC (hexanes/EtOAc=1/0.3) analysis. The reaction mixture was then poured into a 1 L Erlenmeyer flask containing DCM (400 mL) and EtOAc (400 mL). The solution was then passed through a celite plug, and rinsed several times with DCM until all the organic material had passed through. The solution was then concentrated to dryness, re-dissolved in DCM, absorbed into silica gel, and separated over silica column to give 5-bromo-4,6-dimethyl-2-benzofuran-1(3H)-one. LC-MS: M+1=242

Provenance & Evidence