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  1. A novel class of polymers and oligomers of chiral folding chirality has been designed and synthesized, showing structurally compacted triple-column/multiple-layer frameworks. Both uniformed and differentiated aromatic chromophoric units were successfully constructed between naphthyl piers of this framework. Screening monomers, catalysts, and catalytic systems led to the success of asymmetric catalytic Suzuki-Miyaura polycouplings. Enantio- and diastereochemistry were unambiguously determined by X-ray structural analysis and concurrently by comparison with a similar asymmetric induction by the same catalyst in the asymmetric synthesis of a chiral three-layered product. The resulting chiral polymers exhibit intense fluorescence activity in a solid form and solution under specific wavelength irradiation. 
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  3. Abstract

    The first example of PdII‐catalyzed γ‐C(sp3)−H functionalization of aliphatic and benzoheteroaryl aldehydes has been developed using a transient ligand and an external ligand, concurrently. A wide array of γ‐arylated aldehydes were readily accessed without preinstalling internal directing groups. The catalytic mechanism was studied by performing deuterium‐labelling experiments, which indicated that the γ‐C(sp3)−H bond cleavage is the rate‐limiting step during the reaction process. This reaction could be performed on a gram scale, and also demonstrated its potential application in the synthesis of new mechanofluorochromic materials with blue‐shifted mechanochromic properties.

     
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  4. Abstract

    The first example of PdII‐catalyzed γ‐C(sp3)−H functionalization of aliphatic and benzoheteroaryl aldehydes has been developed using a transient ligand and an external ligand, concurrently. A wide array of γ‐arylated aldehydes were readily accessed without preinstalling internal directing groups. The catalytic mechanism was studied by performing deuterium‐labelling experiments, which indicated that the γ‐C(sp3)−H bond cleavage is the rate‐limiting step during the reaction process. This reaction could be performed on a gram scale, and also demonstrated its potential application in the synthesis of new mechanofluorochromic materials with blue‐shifted mechanochromic properties.

     
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  5. Abstract

    Arylation of carbonyls, one of the most common approaches toward alcohols, has received tremendous attention, as alcohols are important feedstocks and building blocks in organic synthesis. Despite great progress, there is still a great gap to develop an ideal arylation method featuring mild conditions, good functional group tolerance, and readily available starting materials. We now show that electrochemical arylation can fill the gap. By taking advantage of synthetic electrochemistry, commercially available aldehydes (ketones) and benzylic alcohols can be readily arylated to provide a general and scalable access to structurally diverse alcohols (97 examples, >10 gram‐scale). More importantly, convergent paired electrolysis, the ideal but challenging electrochemical technology, was employed to transform low‐value alcohols into more useful alcohols. Detailed mechanism study suggests that two plausible pathways are involved in the redox neutral α‐arylation of benzylic alcohols.

     
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  6. Abstract

    Arylation of carbonyls, one of the most common approaches toward alcohols, has received tremendous attention, as alcohols are important feedstocks and building blocks in organic synthesis. Despite great progress, there is still a great gap to develop an ideal arylation method featuring mild conditions, good functional group tolerance, and readily available starting materials. We now show that electrochemical arylation can fill the gap. By taking advantage of synthetic electrochemistry, commercially available aldehydes (ketones) and benzylic alcohols can be readily arylated to provide a general and scalable access to structurally diverse alcohols (97 examples, >10 gram‐scale). More importantly, convergent paired electrolysis, the ideal but challenging electrochemical technology, was employed to transform low‐value alcohols into more useful alcohols. Detailed mechanism study suggests that two plausible pathways are involved in the redox neutral α‐arylation of benzylic alcohols.

     
    more » « less