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Azo-triazolide bis-cyclometalated Ir(iii) complexes via cyclization of 3-cyanodiarylformazanate ligands.

ABSTRACT: In this work we describe the synthesis of sterically encumbered 1,5-diaryl-3-cyanoformazanate bis-cyclometalated iridium(iii) complexes, two of which undergo redox-neutral cyclization during the reaction to produce carbon-bound 2-aryl-4-arylazo-2H-1,2,3-triazolide ligands. This transformation offers a method for accessing 2-aryl-4-arylazo-2H-1,2,3-triazolide ligands, a heretofore unreported class of chelating ligands. One formazanate complex and both triazolide complexes are structurally characterized by single-crystal X-ray diffraction, with infrared spectroscopy being the primary bulk technique to distinguish the formazanate and triazolide structures. All complexes are further characterized by UV-Vis absorption spectroscopy and cyclic voltammetry, with the triazolide compounds having similar frontier orbital energies to the formazanate complexes but much less visible absorption.

SUBMITTER: Mu G

PROVIDER: S-EPMC7328346 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Azo-triazolide bis-cyclometalated Ir(iii) complexes via cyclization of 3-cyanodiarylformazanate ligands.

Mu Ge G Wen Zhili Z Wu Judy I-Chia JI Teets Thomas S TS

Dalton transactions (Cambridge, England : 2003) 20191127 12

In this work we describe the synthesis of sterically encumbered 1,5-diaryl-3-cyanoformazanate bis-cyclometalated iridium(iii) complexes, two of which undergo redox-neutral cyclization during the reaction to produce carbon-bound 2-aryl-4-arylazo-2H-1,2,3-triazolide ligands. This transformation offers a method for accessing 2-aryl-4-arylazo-2H-1,2,3-triazolide ligands, a heretofore unreported class of chelating ligands. One formazanate complex and both triazolide complexes are structurally charact ...[more]

PMID: 31774084

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