3 years ago

Chirality of the trisubstituted nitrogen center – XRD, dynamic NMR, and DFT investigation of 1,2-dihydrobenzo[e][1,2,4]triazine derivatives

Chirality of the trisubstituted nitrogen center – XRD, dynamic NMR, and DFT investigation of 1,2-dihydrobenzo[e][1,2,4]triazine derivatives
Molecular structures of two 1-aryl-2-benzyloxycarbonyl-1,2-dihydrobenzo[e][1,2,4]triazines 1 were established by single crystal XRD and compared to those of 4-benzyloxycarbonyl (2) and 4-benzyl (4) analogues. The structures revealed a highly pyramidalized asymmetric N(1) center stabilized by steric interactions in 1, but not in 2 and 3. Activation parameters for enantiomer interconversion were obtained by DNMR methods in C6D5Cl: ΔH = 18.1(1) kcal mol−1, ΔS = −0.6(1) cal mol−1 K−1 for Ar = Ph (1a) and ΔH = 18.6(4) kcal mol−1, ΔS = 5.2(6) cal mol−1 K−1 for Ar = 2-anisyl (1b). DFT computational investigation of the origin of the interconversion barrier on model compounds revealed steric destabilization of the inversion TS.

Publisher URL: www.sciencedirect.com/science

DOI: S0040402017305070

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.