Efficient multi-click approach to well-defined two-faced octasilsesquioxanes: the first perfect Janus nanocube

The preparation of the first structurally well-defined Janus nanocube showing two chemically distinct opposed faces is described. The synthetic approach is based on a highly efficient and symmetrycontrolled CuAAC functionalization of an octa-azido cubic silsesquioxane with a conformationally constrained tetra-alkyne with an appropriate spatial orientation of the triple bonds.
with two sets of orthogonally reactive functional groups. We gratefully acknowledge financial support by the Spanish Ministerio de Ciencia e Innovación (project MAT2010-20646- C04-03) and Ministerio de Economía y Competitividad (project MAT2014-51937-C3-1-P). We also acknowledge the Spanish Ministerio de Economía y Competitividad for a FPI contract to A. B., and CSIC for a JAEDOC contract to J. R. S. and a JAEPRE contract to M. E. P.-O., and for support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).