2,2'-Bipyridyl-Embedded Cycloparaphenylenes as a General Strategy To Investigate Nanohoop-Based Coordination Complexes

J Am Chem Soc. 2017 Mar 1;139(8):2936-2939. doi: 10.1021/jacs.7b00359. Epub 2017 Feb 21.

Abstract

Because of their unique cyclic architectures, tunable electronic properties, and supramolecular chemistries, cycloparaphenylenes (CPPs) have the potential to act as a new class of ligands for coordination cages, metal-organic frameworks, and small-molecule transition-metal complexes. However, currently there is no general strategy to coordinate the cyclic framework to a variety of metal centers. We report here a general and scalable synthetic strategy to embed 2,2'-bipyridine units into the backbone of CPPs. We use this approach to synthesize a 2,2'-bipyridine-embedded [8]CPP, which we show can successfully coordinate to both Pd(II) and Ru(II) metal centers. The resulting coordination complexes, a Pd(II)-nanohoop dimer and a bis(bipyridyl)ruthenium(II)-functionalized nanohoop, show unique solid-state and photophysical properties. This work provides a proof of concept for a general strategy to use nanohoops and their derivatives as a new class of ligands.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.