1-Hydroxybenzotriazole → (trans)-1-(5-Bromo-benzofuran-2-yl-carbonyl)-4-(4-fluorobenzyl)-2,5-dimethylpiperazine

Participants

Reaction Steps

A mixture of (trans)-1-(4-fluorobenzyl)-2,5-dimethyl-piperazine (220 mg, 1.0 mmol), 5-bromo-1-benzofuran-2-carboxylic acid (342 mg, 1.5 mmol), 1-hydroxybenzotriazol (200 mg, 1.5 mmol) and N-cyclohexylcarbodiimide, N′-methylpolystyrene (167 g, 3.0 mmol of the resin with a loading of 1.8 mmol/g) in CHCl3 was heated under 5 minutes at 110° C. in a microwave oven The mixture was allowed to attain room temperature. TBD-methyl polystyrene (1000 mg, 3 mmol of the resin with a loading of 2.9 mmol/g) was added and the mixture was agitated over night. Both resins were filtered off and washed with CHCl3 and EtOAc. The filtrate was concentrated in vacuo and the residue was submitted to flash column chromatography (toluene→toluene: EtOAc, 20:1→toluene: EtOAc, 1:1) to give the title product in 93% yield.

Provenance & Evidence