One-pot syntheses of rhena-2-benzopyrylium complexes with a fused metallacyclopropene unit†
Abstract
A convenient synthetic route to polycyclic metallaaromatics containing main-group heteroatoms has been developed. The first cyclopropametalla-2-benzopyrylium complexes 2–4, the rhena-analogues of pyrylium, are isolated and characterized. Structural analysis and DFT calculations show that the metalla-oxa polycyclic structures have both π-aromaticity and σ-aromaticity.