Synthesis and luminescent properties of pyrenylvinylene-substituted tripylborane

A novel luminescent compound, bis((E)-2-pyren-1-yl-vinyl)-2,4,6-triisopropylphenylborane (3) was synthesized by hydroboration reaction and was fully characterized. The obtained compound was further investigated by single-crystal X-ray diffraction analysis and DFT calculations. The extended structure tells us their herringbone structures with closely faced pairs of the molecules. Comparing the photoluminescent spectra between solution-state and solid state, the spectrum of the solid state of the compound 3 exhibited dramatically red-shifted fluorescent emission. This change also supports the efficient π-stacking behavior of the compound 3.