Electron‐Rich, Lewis Acidic Diborane Meets N‐Heterocyclic Aromatics: Formation and Electron Transfer in Cyclophane Boranes
Anna Widera, Erik Filbeck, Hubert Wadepohl, Elisabeth Kaifer, Hans‐Jörg Himmel
Abstract
Herein reported are the reactions of an electron-rich, Lewis acidic diborane with N-heterocyclic aromatics to give first members of an unprecedented family of highly charged cationic cyclophanes with diboranyl units. Tetracationic cyclophanes with 4,4'-bipyridine/ 1,2-bis(4-pyridyl)ethylene and diboranyl units were synthesized and their redox chemistry was studied. Cyclisation of two diboranyl and two pyrazine units is accompanied by electron transfer from the diboranyl unit to the pyrazine. Our results pave the way for the integration of redox-active diboranyl units into cyclophanes and supramolecular structures.
Topics & Concepts
DiboraneCyclophaneChemistryPyrazineBoranesCationic polymerizationRedoxElectron transferSupramolecular chemistryLewis acids and basesPolymer chemistryMedicinal chemistryPhotochemistryOrganic chemistryBoronCrystal structureCatalysisOrganoboron and organosilicon chemistryBoron Compounds in ChemistrySynthesis and Properties of Aromatic Compounds