Evidence of boride-borylene ligand-tautomerism leading to a remote C-C-bond and concomitant boryl ligand formation.

The formation of a rhodium pincer-type complex with a boron-based donor ligand and its reactivity are reported. The starting complex contains a formal borylene moiety, stabilised by two pyridine substituents. Quantum chemical investigations indicate the possibility of deprotonation of the central donor group of the type pyBH in this complex.