Chromium-Templated Benzannulation and Haptotropic Metal Migration

Abstract

This review highlights the recent development in intramolecular migration of metal templates along fused arene skeletons. The focus is on the haptotropic rearrangement of a Cr(CO)₃-fragment along polycyclic aromatic π-systems. The straightforward and regioselective synthesis of arene-Cr(CO)₃ complexes via chromium-templated [3+2+1]-benzannulation is discussed in the context of mechanistic and synthetic aspects. Proper tuning of the arene substitution pattern and the template coligand sphere allows the design of the haptotropic rearrangement for an application in novel organometallic molecular switches.