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Synthesis of IrIII Hydrido Complexes by Oxidative Addition of Halogenated Theophylline and Adenine Derivatives.

ABSTRACT: The IrIII hydrido complexes [1] and [2] have been synthesized by the regioselective oxidative addition of the N7-H bond of 8-halogenotheophyllines to [IrCl(coe)2]2 in the presence of PPh3. The use of dppf in this reaction yielded the bimetallic IrIII/FeII hydrido complexes [3] and [4]. X-ray diffraction studies confirmed that complexes [1]-[4] feature a theophyllinato ligand coordinated to the metal center in the rarely observed, chelating fashion via the N7 and O1 atoms. In addition, 8-bromoadenine reacts with [IrCl(coe)2]2 in the presence of PPh3 to form the IrIII hydrido complex [5] which features one anionic 8-bromoadeninato and one neutral 8-bromoadenine ligand linked by an intramolecular hydrogen bond. Complex [5] was characterized by high-resolution mass spectrometry and an X-ray diffraction analysis but could not be analyzed by nuclear magnetic resonance spectroscopy because of its low solubility.

SUBMITTER: Blumenberg J

PROVIDER: S-EPMC7366355 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Synthesis of IrIII Hydrido Complexes by Oxidative Addition of Halogenated Theophylline and Adenine Derivatives.

Blumenberg Jonas J Kampert Florian F Hepp Alexander A Hahn F Ekkehardt FE

ACS omega 20200629 27

The IrIII hydrido complexes [1] and [2] have been synthesized by the regioselective oxidative addition of the N7-H bond of 8-halogenotheophyllines to [IrCl(coe)2]2 in the presence of PPh3. The use of dppf in this reaction yielded the bimetallic IrIII/FeII hydrido complexes [3] and [4]. X-ray diffraction studies confirmed that complexes [1]-[4] feature a theophyllinato ligand coordinated to ...[more]

PMID: 32685865

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