Trapping of a Borirane Intermediate in the Reductive Coupling of an Arylborane to a Diborene
Alexander Hermann, Merle Arrowsmith, Daniel E. Trujillo‐González, J. Óscar C. Jiménez‐Halla, Alfredo Vargas, Holger Braunschweig
Abstract
The reductive coupling of a N-heterocyclic carbene (NHC)-stabilized aryldibromoborane yields a mixture of trans- and cis-diborenes in which the aryl groups are coplanar with the diborene core. Under dilute reduction conditions two diastereomers of a borirane–borane intermediate are isolated, which upon further reduction give rise to the aforementioned diborene mixture. DFT calculations suggest a mechanism proceeding via nucleophilic attack of a dicoordinate borylene intermediate on the aryl ring and subsequent intramolecular B–B bond formation.
Topics & Concepts
ChemistryTrappingCoupling (piping)Reductive eliminationComputational chemistryPhotochemistryChemical physicsOrganic chemistryMetallurgyCatalysisMaterials scienceEcologyBiologyOrganoboron and organosilicon chemistryCoordination Chemistry and OrganometallicsSynthesis and characterization of novel inorganic/organometallic compounds