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Electrochemically Driven Swinging of a Nitrobenzyl Pendant Arm in a Nickel Scorpionand Complex.

ABSTRACT: A radical anion -NO₂ ^.- is formed upon an electrochemically reversible one-electron reduction of the square-planar Ni^II complex of N-nitrobenzylcyclam. The -NO₂ ^.- group goes to occupy an axial position of the metal ion, thus establishing a significant electronic interaction with the metal center. In particular, the ESR spectrum supports the occurrence of an electron transfer from -NO₂ ^.- to the metal, which therefore presents a significant Ni^I character. On re-oxidation, the nitrobenzyl side chain detaches and the Ni^II complex is restored, providing an example of a fully reversible redox driven intramolecular motion.

SUBMITTER: Ciarrocchi C

PROVIDER: S-EPMC9311437 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Electrochemically Driven Swinging of a Nitrobenzyl Pendant Arm in a Nickel Scorpionand Complex.

Ciarrocchi Carlo C Fabbrizzi Luigi L Licchelli Maurizio M Taglietti Angelo A

Chemistry (Weinheim an der Bergstrasse, Germany) 20220329 26

A radical anion -NO2 .- is formed upon an electrochemically reversible one-electron reduction of the square-planar NiII complex of N-nitrobenzylcyclam. The -NO2 .- group goes to occupy an axial position of the metal ion, thus establishing a significant electronic interaction with the metal center. In particular, the ESR spectrum supports the occurrence of an electron transfer from -NO2 .- to the metal, which therefore p ...[more]

PMID: 35234313

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