A crystalline cyclic (alkyl)(amino)carbene with a 1,1'-ferrocenylene backbone.

Cyclic (alkyl)(amino)carbenes with a 1,1'-ferrocenylene backbone (fcCAACs) are established as an original family by the preparation of a crystalline congener. The C carbene bond angle is unprecedentedly wide for a CAAC, causing an exceptionally pronounced ambiphilicity. The redox-active backbone opens the door to unconventional metalloradicals and oligoradicals.