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Element-Element Bond Formation upon Oxidation and Reduction.

ABSTRACT: The redox chemistry of [(Cp'''Co)2 (?,?2 :?2 -E2 )2 ] (E=P (1), As (2); Cp'''=1,2,4-tri(tert-butyl)cyclopentadienyl) was investigated. Both compounds can be oxidized and reduced twice. That way, the monocations [(Cp'''Co)2 (?,?4 :?4 -E4 )][X] (E=P, X=BF4 (3?a), [FAl] (3?b); E=As, X=BF4 (4?a), [FAl] (4?b)), the dications [(Cp'''Co)2 (?,?4 :?4 -E4 )][TEF]2 (E=P (5), As (6)), and the monoanions [K(18-c-6)(dme)2 ][(Cp'''Co)2 (?,?4 :?4 -E4 )] (E=P (7), As (8)) were isolated. Further reduction of 7 leads to the dianionic complex [K(18-c-6)(dme)2 ][K(18-c-6)][(Cp'''Co)2 (?,?3 :?3 -P4 )] (9), in which the cyclo-P4 ligand has rearranged to a chain-like P4 ligand. Further reduction of 8 can be achieved with an excess of potassium under the formation of [K(dme)4 ][(Cp'''Co)2 (?,?3 :?3 -As3 )] (10) and the elimination of an As1 unit. Compound 10 represents the first example of an allylic As3 ligand incorporated into a triple-decker complex.

SUBMITTER: Piesch M

PROVIDER: S-EPMC7216884 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Element-Element Bond Formation upon Oxidation and Reduction.

Piesch Martin M Graßl Christian C Scheer Manfred M

Angewandte Chemie (International ed. in English) 20200313 18

The redox chemistry of [(Cp'''Co)2 (μ,η2 :η2 -E2 )2 ] (E=P (1), As (2); Cp'''=1,2,4-tri(tert-butyl)cyclopentadienyl) was investigated. Both compounds can be oxidized and reduced twice. That way, the monocations [(Cp'''Co)2 (μ,η4 :η4 -E4 )][X] (E=P, X=BF4 (3 a), [FAl] (3 b); E=As, X=BF4 (4 a), [FAl] (4 b)), the dications [(Cp'''Co)2 (μ,η4 :η4 -E ...[more]

PMID: 32017349

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