Multi-component reactions involving group 6 Fischer carbene complexes: a source of inspiration for future catalytic transformations

The ability of heteroatom stabilized Fischer carbene complexes (FCCs) to participate in multicomponent reactions (MCRs) has become a characteristic of such organometallics, particularly of chromiumcarbenes. This feature article updates the main results in this field during the last lustrum, highlighting the ability of FCCs for the construction of densely functionalized frameworks, mainly through the successive incorporation of unsaturated moieties (alkynes, CO ligands,...) in a sequential manner. Examples where up to seven components are coupled will be presented. An overview of multi component reactions (MCRs) of Fischer carbene complexes (FCCs) with alkynes, or allenes, and/or other different reagents is presented.