The synthesis of new 60° organometallic subunits and self-assembly of three-dimensional M3L2 trigonal-bipyramidal cages

By employing the coupling reaction of trans-PtI2(Et-3)(2) 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 M3L2 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.