Synthesis and hydrogenation of polycyclic aromatic hydrocarbon-substituted diborenes via uncatalysed hydrogenative B-C bond cleavage.

ABSTRACT: The classical route to the PMe₃-stabilised polycyclic aromatic hydrocarbon (PAH)-substituted diborenes B₂Ar₂(PMe₃)₂ (Ar = 9-phenanthryl 7-Phen; Ar = 1-pyrenyl 7-Pyr) via the corresponding 1,2-diaryl-1,2-dimethoxydiborane(4) precursors, B₂Ar₂(OMe)₂, is marred by the systematic decomposition of the latter to BAr(OMe)₂ during reaction workup. Calculations suggest this results from the absence of a second ortho-substituent on the boron-bound aryl rings, which enables their free rotation and exposes the B-B bond to nucleophilic attack. 7-Phen and 7-Pyr are obtained by the reduction of the corresponding 1,2-diaryl-1,2-dichlorodiborane precursors, B₂Ar₂Cl₂

SUBMITTER: Okorn A 

PROVIDER: S-EPMC9242019 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature