3 years ago

Intramolecular N→B Coordination as a Stabilizing Scaffold for π-Conjugated Radical Anions with Tunable Redox Potentials

Intramolecular N→B Coordination as a Stabilizing Scaffold for π-Conjugated Radical Anions with Tunable Redox Potentials
Benjamin Rudolf, Antonio J. Pierik, Frank Pammer, Dominique F. Bechtel, Yu Sun, Markus Grandl
In this work we report on a preparative strategy that allows the facile tuning of the electron affinities of π-conjugated organic n-type materials via intramolecular N→B coordination: 2-fold hydroboration of a pyrazine-derived substrate with 9H-borabicyclo[3.3.1]nonane (9H-BBN) and Piers’ borane ((C6F5)2BH) furnishes the intramolecularly N→B-coordinated compounds PzBBN and PzBPF in high yield. For each borane racemic mixtures of the respective chiral derivatives and achiral meso compounds have been isolated, and their electrochemical, optical, and structural properties have been investigated and complemented by DFT calculations. The boranes exhibit high electron affinities with electrochemical LUMO energy levels of −3.69 and −4.30 eV, respectively. The corresponding radical anions PzBBN•– and PzBPF•– can be reversibly generated and are stable in solution at ambient temperature. Analysis of the radical species by EPR spectroscopy and single-crystal analysis of [PzBPF]•–[CoCp2]+ allowed further corroboration of the π-delocalized nature of these radicals.

Publisher URL: http://dx.doi.org/10.1021/acs.organomet.6b00916

DOI: 10.1021/acs.organomet.6b00916

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.