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Single Electron Transfer to Diazomethane-Borane Adducts Prompts C-H Bond Activations.

ABSTRACT: While (Ph₂ CN₂ )B(C₆ F₅ )₃ is unstable, single electron transfer from Cp*₂ Co affords the isolation of stable products [Cp*₂ Co][Ph₂ CNNHB(C₆ F₅ )₃ ] 1 and [Cp*Co(C₅ Me₄ CH₂ B(C₆ F₅ )₃ )] 2. The analogous combination of Ph₂ CN₂ and BPh₃ showed no evidence of adduct formation and yet single electron transfer from Cp*₂ Cr affords the species [Cp*₂ Cr][PhC(C₆ H₄ )NNBPh₃ ] 3 and [Cp*₂ Cr][Ph₂ CNNHBPh₃ ] 4. Computations showed both reactions proceed via transient radical anions of the diphenyldiazomethane-borane adducts to effect C-H bond activations.

SUBMITTER: Cao LL

PROVIDER: S-EPMC6972512 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Single Electron Transfer to Diazomethane-Borane Adducts Prompts C-H Bond Activations.

Cao Levy L LL Zhou Jiliang J Qu Zheng-Wang ZW Stephan Douglas W DW

Angewandte Chemie (International ed. in English) 20191030 51

While (Ph2 CN2 )B(C6 F5 )3 is unstable, single electron transfer from Cp*2 Co affords the isolation of stable products [Cp*2 Co][Ph2 CNNHB(C6 F5 )3 ] 1 and [Cp*Co(C5 Me4 CH2 B(C6 F5 )3 )] 2. The analogous combination of Ph2 CN2 and BPh3 showed no evidence of adduct formation and ...[more]

PMID: 31589360

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