3 years ago

Synthesis, Thermochemistry, Bonding, and 13C NMR Chemical Shift Analysis of a Phosphorano-Stabilized Carbene of Thorium

Synthesis, Thermochemistry, Bonding, and 13C NMR Chemical Shift Analysis of a Phosphorano-Stabilized Carbene of Thorium
Guang Wu, Danil E. Smiles, Trevor W. Hayton, Peter Hrobárik
Reaction of the Th(IV) metallacycle [Th(CH2SiMe2NSiMe3)(NR2)2] (1; R = SiMe3), with Ph3P═CH2 affords the Th(IV) carbene [Th(CHPPh3)(NR2)3] (2) in good yield. In solution, complex 2 exists in equilibrium with complex 1 and free ylide, Ph3P═CH2. The thermodynamic parameters of this equilibrium were probed using variable-temperature NMR spectroscopy, and these results are compared to those collected for the isostructural U(IV) complex [U(CHPPh3)(NR2)3]. X-ray diffraction studies, together with NMR spectroscopic data and DFT calculations, provide clear evidence for actinide–carbon multiple bonding in the title complex 2, which features the shortest Th–C distance measured thus far. This interaction is best characterized as a strongly polarized σ(Th–C) bond augmented by a three-center two-electron π(Th–C–P)-type interaction. In addition, 13C NMR chemical shifts of carbon atoms bonded to the thorium center were identified as quantitative measures of the An–C bond covalency for a series of structurally related Th carbenes.

Publisher URL: http://dx.doi.org/10.1021/acs.organomet.7b00202

DOI: 10.1021/acs.organomet.7b00202

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.