Carbon-carbon (C-C) bonds are fundamental building blocks that make up organic compounds. Selective cleavage and functionalization of C-C bonds are important in organic chemistry, biodegradation, and oil industry.
However, functionalization of C-C bonds by controlled cleavage remains difficult and challenging because they are inert.
Recently, a research group led by Prof. DAI Wen from the Dalian Institute of Chemical Physics of the Chinese Academy of Sciences developed heterogeneous cobalt nanoparticles catalyst with dioxygen as the oxidant to break successive C-C bonds in alcohols to form esters with one or multiple carbon atoms less.
They prepared heterogeneous Co-NC catalysts for the aerobic oxidative successive C-C bond cleavage of various functionality aromatic, aliphatic, heterocyclic, allylic, propargylic primary and secondary alcohols to one or multiple carbon atoms shorter esters with O2 as the oxidant. The catalyst was used for seven times without any decrease in activity.
Characterization and control experiments disclosed that cobalt nanoparticles were responsible for the successive cleavage of C-C bonds to achieve excellent catalytic activity, while the presence of Co-Nx had just the opposite effect.
Preliminary mechanistic studies revealed that a sequence reaction including stepwise oxidation/nucleophilic addition/C-C bond cleavage was involved in this process.
This work not only realizes successive cleavage adjacent -(C-C)n- bonds, but also provides a new practical method for directly accessing ester through C-C bond cleavage in alcohols.
The study, published in Angew. chem. int. Ed. on August 24, was supported by National Natural Science Foundation of China.
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