Sulfamic Acid → 2-[4-(tert-Butoxycarbonyl)piperazin-1-yl]benzoic acid

Participants

Reaction Conditions

Reaction Steps

4-(2-Formyl-phenyl)-piperazine-1-carboxylic acid tert-butyl ester (0.50 g, 1.72 mmol) is dissolved in 80 mL of dioxane and 20 mL of H2O. The mixture is cooled to 4° C. and then sulfamic acid (1.36 g, 14.00 mmol) is added in one portion. The mixture is stirred for an additional 30 min and then 3 mL of a solution of NaClO2 (0.343 g, 3.80 mmol) is added in a drop-wise portion. The reaction is quenched by the addition of 50 mL of H2O and 50 mL of brine. The resulting mixture is extracted with 3×100 mL of CH2Cl2. The combined organic phase is washed with 2×50 mL of brine, dried with MgSO4, filtered and concentrated to give 500 mg of 4-(2-carboxy-phenyl)-piperazine-1-carboxylic acid tert-butyl ester.

Provenance & Evidence