A series of ethynylated silanes, including tetraethynylsilane, was treated with tetraphenylcyclopentadienone at 300 °C under microwave irradiation to give the aromatized Diels-Alder adducts as sterically encumbered mini-dendrimers with up to 20 benzene rings. The sterically most congested adducts display red-shifted emission through intramolecular π-π interactions in the excited state.
Keywords: Diels-Alder reaction; dendrimer; ethynyl; oligophenyl; silane.
© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.