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Unlocking the Nucleophilicity of Strong Alkyl C-H Bonds via Cu/Cr Catalysis.

ABSTRACT: Direct functionalization of inert C-H bonds is one of the most attractive yet challenging strategies for constructing molecules in organic chemistry. Herein, we disclose an unprecedented and Earth abundant Cu/Cr catalytic system in which unreactive alkyl C-H bonds are transformed into nucleophilic alkyl-Cr(III) species at room temperature, enabling carbonyl addition reactions with strong alkyl C-H bonds. Various aryl alkyl alcohols are furnished under mild reaction conditions even on a gram scale. Moreover, this new radical-to-polar crossover approach is further applied to the 1,1-difunctionalization of aldehydes with alkanes and different nucleophiles. Mechanistic investigations reveal that the aldehyde not only acts as a reactant but also serves as a photosensitizer to recycle the Cu and Cr catalysts.

SUBMITTER: Peng P

PROVIDER: S-EPMC10141608 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature

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Unlocking the Nucleophilicity of Strong Alkyl C-H Bonds via Cu/Cr Catalysis.

Peng Pan P Zhong Yifan Y Zhou Cong C Tao Yongsheng Y Li Dandan D Lu Qingquan Q

ACS central science 20230327 4

Direct functionalization of inert C-H bonds is one of the most attractive yet challenging strategies for constructing molecules in organic chemistry. Herein, we disclose an unprecedented and Earth abundant Cu/Cr catalytic system in which unreactive alkyl C-H bonds are transformed into nucleophilic alkyl-Cr(III) species at room temperature, enabling carbonyl addition reactions with strong alkyl C-H bonds. Various aryl alkyl alcohols are furnished under mild reaction conditions even on a gram scal ...[more]

PMID: 37122460

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