1,3,5-Triaza-7-Phosphaadamantane (PTA) as a 31P NMR Probe for Organometallic Transition Metal Complexes in Solution

Molecules. 2021 Mar 4;26(5):1390. doi: 10.3390/molecules26051390.

Abstract

Due to the rigid structure of 1,3,5-triaza-7-phosphaadamantane (PTA), its 31P chemical shift solely depends on non-covalent interactions in which the molecule is involved. The maximum range of change caused by the most common of these, hydrogen bonding, is only 6 ppm, because the active site is one of the PTA nitrogen atoms. In contrast, when the PTA phosphorus atom is coordinated to a metal, the range of change exceeds 100 ppm. This feature can be used to support or reject specific structural models of organometallic transition metal complexes in solution by comparing the experimental and Density Functional Theory (DFT) calculated values of this 31P chemical shift. This approach has been tested on a variety of the metals of groups 8-12 and molecular structures. General recommendations for appropriate basis sets are reported.

Keywords: 31P NMR; condensed matter; external electric field; polarizable continuum model; reaction field; solvent effect.

MeSH terms

  • Adamantane / analogs & derivatives*
  • Adamantane / chemistry
  • Catalysis
  • Coordination Complexes / chemistry*
  • Magnetic Resonance Spectroscopy / methods*
  • Molecular Probes / analysis*
  • Molecular Structure
  • Organometallic Compounds / chemistry*
  • Organophosphorus Compounds / chemistry*
  • Phosphorus / analysis*
  • Transition Elements / chemistry*
  • Water

Substances

  • 1,3,5-triaza-7-phosphaadamantane
  • Coordination Complexes
  • Molecular Probes
  • Organometallic Compounds
  • Organophosphorus Compounds
  • Transition Elements
  • Water
  • Phosphorus
  • Adamantane