Ethyl Acetate → 1,1-dimethylethyl (2S)-2-methyl-4-{[2-methyl-4-(trifluoromethyl)phenyl]sulfonyl}-1-piperazinecarboxylate

Participants

Reaction Conditions

Reaction Steps

A solution of 1,1-dimethylethyl(2S)-4-{[2-bromo-4-(trifluoromethyl)phenyl]sulfonyl}-2-methyl-1-piperazinecarboxylate (1.00 g, 2.05 mmol) (may be prepared as described in Description 26), potassium carbonate (0.737 g, 5.34 mmol) in 1,4-dioxane (43 ml) were stirred for 5 min then trimethylboroxin (0.743 ml, 5.34 mmol) and Pd(Ph3P)4 (0.403 g, 0.349 mmol) were added and the reaction mixture heated at 100° C. overnight. EtOAc (100 ml) was added then the mixture washed aqueous sodium bicarbonate (100 ml), water (100 ml) and concentrated under vacuum. Flash chromatography (silica; linear gradient (0-20%) EtOAc in isohexane) gave 1,1-dimethylethyl(2S)-2-methyl-4-{[2-methyl-4-(trifluoromethyl)phenyl]sulfonyl}-1-piperazinecarboxylate (0.785 g).

Provenance & Evidence