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A Mesoionic Diselenolene Anion and the Corresponding Radical Dianion.

ABSTRACT: Dichalcogenolenes are archetypal redox non-innocent ligands with numerous applications. Herein, a diselenolene ligand with fundamentally different electronic properties is described. A mesoionic diselenolene was prepared by selenation of a C2-protected imidazolium salt. This ligand is diamagnetic, which is in contrast to the paramagnetic nature of standard dichalcogenolene monoanions. The new ligand is also redox-active, as demonstrated by isolation of a stable diselenolene radical dianion. The unique electronic properties of the new ligand give rise to unusual coordination chemistry. Thus, preparation of a hexacoordinate aluminum tris(diselenolene) complex and a Lewis acidic aluminate complex with two ligand-centered unpaired electrons was achieved.

SUBMITTER: Dong Z

PROVIDER: S-EPMC9322424 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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A Mesoionic Diselenolene Anion and the Corresponding Radical Dianion.

Dong Zhaowen Z Sienkiewicz Andrzej A Suleymanov Abdusalom A AA Berton Cesare C Fadaei-Tirani Farzaneh F Scopelliti Rosario R Severin Kay K

Chemistry (Weinheim an der Bergstrasse, Germany) 20220421 32

Dichalcogenolenes are archetypal redox non-innocent ligands with numerous applications. Herein, a diselenolene ligand with fundamentally different electronic properties is described. A mesoionic diselenolene was prepared by selenation of a C2-protected imidazolium salt. This ligand is diamagnetic, which is in contrast to the paramagnetic nature of standard dichalcogenolene monoanions. The new ligand is also redox-active, as demonstrated by isolation of a stable diselenolene radical dianion. The ...[more]

PMID: 35388932

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