Spatial race under low oxygen conditions requires solid mild propellants to be used. Therefore, we study the catalytic effect of the previously reported [trans-Cu(mu-OH)(mu-dmpz)](6) complex on the thermal decomposition of ammonium perchlorate by a differential scanning calorimetry (DSC) technique. The copper compound causes a decrease of ammonium perchlorate's decomposition temperature to 372.5 degrees C, consequently increasing the heat release by 576 J.g(-1), when used in a 5 wt% as burning rate (BR) catalyst. It must be remarked that, the [trans-Cu (mu-OH)(mu-dmpz)](6) complex presents a superior performance as BR catalyst when compared to nano-metallic oxides. This Cu-(II) compound modifies the decomposition mechanism of ammonium perchlorate, providing the necessary O-2 to accelerate the overall burning process paving the way to the study of copper pyrazolate complexes as BR catalysts.