Structural Snapshots of π‐Arene Bonding in a Gold Germylene Cation

Heavier group 14 element cations exhibit a remarkable reactivity that has typically hampered their isolation. For the few available examples, the role of π‐arene interactions is crucial to provide kinetic stabilization, but dynamic and structural information on those contacts is yet limited. In this study we have accessed the metalogermylenium cation [(PMe(2)Ar(Dipp2))AuGe(Ar(Dipp2))Cl](+) (4(+)) (Ar(Dipp2)=C(6)H(3)‐2,6‐(C(6)H(3)‐2,6‐iPr(2))(2)) that has been structurally characterized with three different non‐coordinating counter anions. These studies provide for the first time dynamic information about the conformational rearrangement that characterizes π‐arene bonding thorough a series of X‐ray diffraction structural snapshots. Computational studies reveal the weak character of the π‐arene bonding (ca. 2 kcal mol(−1)) that can be described as the donation from a π(C=C) bond toward the empty p valence orbital of germanium.