A Square‐Planar Tetracoordinate Oxygen‐Containing Ti4O17 Cluster Stabilized by Two 1, 1′‐Ferrocenedicarboxylato Ligands1. Issue 35 (2nd July 2014)

• Record Type: Journal Article
• Authors: Liu, Zhichang; Lei, Juying; Frasconi, Marco; Li, Xiaohu; Cao, Dennis; Zhu, Zhixue; Schneebeli, Severin T.; Schatz, George C.; Stoddart, J. Fraser
• Is Part Of: Angewandte Chemie international edition. Volume 53:Issue 35(2014)
• Page Start: 9193
• Page End: 9197
• Publication Date: 2014-07-02
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201402603
• Languages: English
• ISSNs: 1433-7851

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>By introducing steric constraints into molecular compounds, it is possible to achieve atypical coordination geometries for the elements. Herein, we demonstrate that a titanium‐oxo cluster [{Ti₄(μ₄‐O)(μ₂‐O)₂}(OPrⁱ)₆(fdc)₂], which possesses a unique edge‐sharing Ti₄O₁₇ octahedron tetramer core, is stabilized by the constraints produced by two orthogonal 1, 1′‐ferrocenedicarboxylato (fdc) ligands. As a result, a square‐planar tetracoordinate oxygen (ptO) can be generated. The bonding pattern of this unusual anti‐van't Hoff/Le Bel oxygen, which has been probed by theoretical calculations, can be described by two horizontally σ‐bonded 2p_{<italic>x</italic>} and 2p_{<italic>y</italic>} orbitals along with one perpendicular nonbonded 2p_{<italic>z</italic>} orbital. While the two ferrocene units are separated spatially by the ptO with an Fe⋅⋅⋅Fe separation of 10.4 Å, electronic communication between them still takes place as revealed by the cluster's two distinct one‐electron electrochemical oxidation processes.</p> </abstract>