The Synthesis of New 60° Organometallic Subunits and Self-Assembly of Three-Dimensional M<sub>3</sub>L<sub>2</sub> Trigonal-Bipyramidal Cages

By employing the coupling reaction of <i>trans</i>-PtI<sub>2</sub>(Et<sub>3</sub>)<sub>2</sub> with C−H bonds in alkynes as the key step, two new 60° organometallic subunits with different size from 3,6-dibromophenanthrene were prepared in reasonable yields. The X-ray structures of both di-Pt(II) diiodide complexes showed that they were indeed suitable candidates for 60° building units. By utilizing these novel linkers as ditopic acceptor subunits, three M<sub>3</sub>L<sub>2</sub> trigonal-bipyramidal (TBP) cages were formed. All three TBP cages were characterized with multinuclear NMR and electrospray ionization mass spectrometry (ESI-MS) along with element analysis.