Title: Synthesis and Characterization of a Metallacyclic Framework with Three Fused Five-membered Rings

Authors: Congqing Zhu, Jingjing Wu, Shenyan Li, Yuhui Yang, Jun Zhu, Xin Lu, Haiping Xia

Abstract:

Polycyclic complexes containing a bridgehead transition metal are interesting species because the transition metal is shared by all the rings simultaneously. In this study, we present a novel osmium-bridgehead system with three fused five-membered rings. This novel framework can be viewed as a 10-atom carbon chain coordinating to the osmium center. In sharp contrast to the nonplanar organic analogue, this unique metallacycle exhibits good planarity which was unambiguously verified by means of X-ray diffraction. Interestingly, preliminary DFT calculations show that the aromaticity in the three 5MRs of these osmatricycles can be easily tuned by the ligand substitution. Finally, the broad UV-vis absorption spectra of these novel polycyclic complexes were also reported.

Full-Link: http://onlinelibrary.wiley.com/doi/10.1002/anie.201704057/abstract