Cu-3(BTC)(2) deactivates by deterioration of its crystal structure during the use of this metal organic framework as catalyst in the synthesis of 2-phenylquinoxaline from phenacylbromide and o-phenylenediamine at room temperature. The material resulting from the use of Cu-3(BTC)(2) as catalyst was characterized by powder XRD, UV-Vis diffuse reflectance spectra and EPR showing that the crystal structure collapses and Cu2+ becomes reduced under the reaction conditions.