Construction of Supramolecular Pyrene-Modified Metallacycles via Coordination-Driven Self-Assembly and Their Spectroscopic Behavior

The
design and self-assembly of novel multipyrene hexagonal metallacycles
via coordination-driven self-assembly is described. By employing newly
designed 120° dipyridine donor and di-Pt­(II) acceptor linkers
substituted with pyrene, a variety of tris- and hexakis­(pyrene) hexagonal
metallacycles with well-defined shape and size were prepared via [3
+ 3] and [6 + 6] self-assembly, respectively, under mild conditions
in high yields. The structures of these novel metallacycles were well
characterized by multinuclear NMR (31P and 1H) spectroscopy, cold-spray ionization time-of-flight mass spectrometry
(CSI-TOF-MS), electrospray ionization time-of-flight mass spectrometry
(ESI-TOF-MS), and elemental analysis. The shape and size of all hexagonal
metallacycles were investigated by the PM6 semiempirical molecular
orbital method. The preliminary study of their spectroscopic behavior
was also carried out. It was found that these pyrene-modified metallacycles
displayed different optical behaviors, which might be caused by the
structural effects.