New perovskite-type compounds La2MlrO6 (M = Mg, Co, Ni, Cu, Zn) have been synthesized by solid state reaction in air. They have been characterized from X-ray diffraction data by means of the Rietveld method. These materials show a monoclinic symmetry (S.G. P2(1)/n). Electron microscopy patterns are indexed as a result of the existence of multitwinning. Electronic conductivity measurements have been carried out, in the range 300-650 K, and a p-type semiconductor behaviour is observed. Activation energies are close to 0.2 eV in all cases. These results are of interest because there is a lack in the knowledge of iridium perovskites and in their properties, which is a contrast to the case of other 4d and 5d elements.