Mixed SAMs of backbone-functionalized tribenzotriquinacenes and alkanethiols: Synthesis, preparation and STM-investigations

We present the synthesis of a backbone-functionalized tribenzotriquinacene (TBTQ) 3, serving as a prototype for TBTQ-based stators comprising thioether anchor groups for self-assembled monolayers on Au-(1 1 1) surfaces. Self-assembled monolayers (SAM) consisting of isolated molecules of the minor component 3 embedded in a close-packed matrix of decanethiol (C10-SH) were prepared, leading to stable monolayers which were characterized by scanning tunneling microscopy (STM) under ambient conditions. The structural features of the highly ordered mixed monolayers point to the fact that isolated TBTQ-headgroups are exposed to the outer monolayer surface, making them available for the interaction with shape-complementary guest molecules.