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Synthesis of a Thiol Building Block for the Crystallization of a Semiconducting Gyroidal Metal-sulfur Framework
Published on: April 9, 2018
A Trithia-Bridged N-Heterotriangulene: The Hitherto Missing Electron Donor
Jan Borstelmann1, Viktoria Gensch2, Dominik Fehn3
1Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany.
Abstract:
The very first representative of trithia-bridged N-heterotriangulene, a triphenylamine with sulfur atoms bridging the ortho-positions, was synthesized by a sequence of regioselective sulfenylation with phthalimidesulfenyl chloride followed by Lewis acid-catalyzed electrophilic cyclization. X-ray crystallography revealed a saddle-shaped geometry of the polycyclic scaffold. UV/Vis absorption spectroscopy and cyclic voltammetry were used to characterize the optoelectronic properties. The title compound is a particularly strong electron donor forming a perfectly stable radical cation, which was analyzed by electron paramagnetic resonance spectroscopy and X-ray crystallography. The electron donor properties were further highlighted by the formation of crystalline donor-acceptor complexes with strong cyano-based acceptors.
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