Incorporation of a First Row Element into the Bridge of a Strained Metallocenophane: Synthesis of a Boron‐Bridged [1]Ferrocenophane

A new record tilt angle [32.4(2)°] is present between the planes of the cyclopentadienyl ligands in the [1]boraferrocenophane 1. This compound is the first [1]ferrocenophane containing a first row element in the bridge. Ring-opening polymerization of 1 leads to cyclic oligomers and insoluble polymer 2.