Protonation and Bromination of an Osmabenzyne: Reactions Leading to the Formation of New Metallabenzynes

The reactivities of benzynes and metal−carbyne complexes are normally associated with the triple bond units. However, we have now found that electrophiles do not attack the formal osmium−carbon triple bond of osmabenzyne complex 1. Instead, 1 undergoes electrophilic substitution reactionsthe typical reactions of aromatic systems.