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Updated: Jul 14, 2026

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Templated synthesis of desymmetrized [2]catenanes with excellent translational selectivity
Yi Liu1, Liana M Klivansky, Saeed I Khan
1The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA. yliu@lbl.gov
Abstract:
Desymmetrized [2]catenanes were synthesized and shown to exhibit excellent translational selectivity. The templated synthesis takes effect from the formation of pseudorotaxanes between pi-rich crown ethers and a pi-deficient pyromellitic (PmI) unit, followed by macrocyclization around the crown ethers with the creation of a bipyridinium (BPy) unit. The crown ethers preferably encircle the BPy unit in the resulting [2]catenanes in both solution and the solid state, as indicated by various spectroscopic analyses.
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