The synthesis of group II–VI colloidal nanocrystals (NCs) has been extensively studied in the past two decades. Since the publication of the fundamental work of Bawendi and coworkers,[1] in which the possibility to obtain high quality nanocrystals by thermal decomposition of dimethyl cadmium in a coordinating solvent was for the first time demonstrated, many studies have been carried out on the preparation of these materials. In 2001 Peng and Peng [2] obtained CdSe and CdTe nanocrystals using an in situ generated complex between cadmium and alkylphosphonic acids as Cd precursor, setting up a less dangerous and toxic procedure and thus opening the route to a more spread research activity in this field. Starting from these materials, many researchers have turned their efforts in manipulating the nanocrystals by chemical modifications of the nanocrystal surface. Relevant interest is due to the potential applications of semiconducting NCs in a variety of areas, spanning from biological labelling and imaging, chemical and biological sensing to photovoltaic devices.[3–5] The nature and the effectiveness of binding of the surrounding shell to the NC surface are of great relevance in view of many applications, because the characteristics of surface groups affect many properties of the final material, such as solubility and stability towards aggregation. Water solubility and longterm stability of the products are among the most commonly desirable properties. The choice of a water-soluble ligand cannot by itself guarantee a water-soluble product, as the coordination process can affect and modify the solubility of the final system.[6] Concerning the …