The synthesis of shape controlled platinum nanoparticles has been investigated the complex Pt-2 (dba)(3) and using a long alkyl chain amine, hexadecylamine (HDA), as stabilizer. The influence of the experimental parameters (reactive gas and solvent nature, stabilizer/metal ratio, reactants concentration, temperature) on the shape of the P-t nanoparticles has been studied. Various shaped platinum nanostructures such as isolated nanoparticles, dendrites or crystalline nanowires were obtained, depending on the reaction conditions. This method takes profit of the mild conditions of chemistry in solution and allows obtaining regular nanostructures, most of them being homogeneous in shape as well as in size (isolated nanoparticles) or diameter/lenght (nanowires). Transmission electron microscopy and wide-angle X-ray scattering were used as characterization techniques. Beside the Knight-shift effect of platinum, NMR solution investigations clearly evidenced the coordination of the anime at the Pt paticles surface and its mobility. The mobility, increased when H-2 is used as reactive gas for the precursor decomposition, favors the particles coalescence into nanowires. This pehnomenon is also favored by the "soft" template character of the amine in particular in toluene solution.