Magnesium Cyanide or Isocyanide?

Ballmann G, Elsen H, Harder S (2019)


Publication Type: Journal article

Publication year: 2019

Journal

DOI: 10.1002/anie.201909511

Abstract

Preference for the binding mode of the CN- ligand to Mg (Mg-CN vs. Mg-NC) is investigated. A monomeric Mg complex with a terminal CN ligand was prepared using the dipyrromethene ligand (DPM)-D-Mes which successfully blocks dimerization. While reaction of ((DPM)-D-Mes)MgN(SiMe3)(2) with Me3SiCN gave the coordination complex ((DPM)-D-Mes)MgN(SiMe3)(2).NCSiMe3, reaction with ((DPM)-D-Mes)Mg(nBu) led to ((DPM)-D-Mes)MgNC.(THF)(2). A Mg-NC/Mg-CN ratio of approximate to 95:5 was established by crystal-structure determination and DFT calculations. IR studies show absorbances for CN stretching at 2085 cm(-1) (Mg-NC) and 2162 cm(-1) (Mg-CN) as confirmed by C-13 labeling. In solution and in the solid state, the CN ligand rotates within the pocket. The calculated isomerization barrier is only 12.0 kcal mol(-1) and the C-13 NMR signal for CN decoalesces at -85 degrees C (Mg-NC: 175.9 ppm, Mg-CN: 144.3 ppm). Experiment and theory both indicate that Mg complexes with the CN- ligand should not be named cyanides but are more properly defined as isocyanides.

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How to cite

APA:

Ballmann, G., Elsen, H., & Harder, S. (2019). Magnesium Cyanide or Isocyanide? Angewandte Chemie International Edition. https://doi.org/10.1002/anie.201909511

MLA:

Ballmann, Gerd, Holger Elsen, and Sjoerd Harder. "Magnesium Cyanide or Isocyanide?" Angewandte Chemie International Edition (2019).

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