Up to date the most promising candidates for ultimate phonon-mediated superconductivity in binary systems are novel crystal structures of a clathrate-type compounds of MH68, MH129 and MH1810 composition (where M is Mg, Sc, La, Ce, Hf, Zr metal) with the developed 3D H-based networks. Among different predicted phases, Fmmm-LaH18 (270 K at 300 GPa), Im-3m-MgH6 (270 K at 350 GPa), Immm-ScH12 (320 K at 300 GPa), Pm-3-MgH12 (375 K at 350 GPa) are stable at pressures, which are achievable in experiment. The main goal of our project is to synthesize the novel hydrogen-enriched lanthanum, scandium and magnesium hydride phases with promising high Tcs and determine their pressure/temperature stability fields. Recently we regularly achieve pressures above 400 GPa by improving the shape of diamond anvils. This allows us to study YH94 at 400 GPa and gold up to 477 GPa11.