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Isolation of a Uranium(III)-Carbon Multiple Bond Complex.

ABSTRACT: Low-valent uranium-element multiple bond complexes remain scarce, though there is burgeoning interest regarding to their bonding and reactivity. Herein, isolation of a uranium(III)-carbon double bond complex [(Cp*)₂ U(CDP)](BPh₄ ) (1) comprising a tridentate carbodiphosphorane (CDP) was reported for the first time. Oxidation of 1 afforded the corresponding U(IV) complex [(Cp*)₂ U(CDP)](BPh₄ )₂ (2). The distance between U and C in 2 is 2.481 Å, indicating the existence of a typical U=C double bond, which is further confirmed by quantum chemical calculations. Bonding analysis suggested that the CDP also serves as both σ- and π-donor in complex 1, though a longer U-C bond (2.666(3) Å) is observed. It implies that 1 is the first isolable mononuclear uranium(III) carbene complex. Moreover, these results suggest that CDPs are promising ligands to establish other low-valent f-block metal-carbon multiple bond complexes.

SUBMITTER: Su W

PROVIDER: S-EPMC8362146 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Isolation of a Uranium(III)-Carbon Multiple Bond Complex.

Su Wei W Ma Yanshun Y Xiang Libo L Wang Junyi J Wang Shuao S Zhao Lili L Frenking Gernot G Ye Qing Q

Chemistry (Weinheim an der Bergstrasse, Germany) 20210610 39

Low-valent uranium-element multiple bond complexes remain scarce, though there is burgeoning interest regarding to their bonding and reactivity. Herein, isolation of a uranium(III)-carbon double bond complex [(Cp*)2 U(CDP)](BPh4 ) (1) comprising a tridentate carbodiphosphorane (CDP) was reported for the first time. Oxidation of 1 afforded the corresponding U(IV) complex [(Cp*)2 U(CDP)](BPh4 )2 (2). The distance between U and C in 2 is 2.481 ...[more]

PMID: 33913186

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