Catalytic Cleavage of C(<i>sp</i><sup>2</sup>)–C(<i>sp</i><sup>2</sup>) Bonds with Rh-Carbynoids
作者:Zhaofeng Wang、Liyin Jiang、Pau Sarró、Marcos G. Suero
DOI:10.1021/jacs.9b08632
日期:2019.10.2
We report a catalytic strategy that generates rhodium-carbynoids by selective diazo activation of designed carbyne sources. We found that rhodium-carbynoid species provoke C(sp2)-C(sp2) bond scission in alkenes by inserting a monovalent carbon unit between both sp2-hybridized carbons. This skeletal remodeling process access synthetically useful allyl cation intermediates that conduct to valuable allylic
Homologation of Alkyl Acetates, Alkyl Ethers, Acetals, and Ketals by Formal Insertion of Diazo Compounds into a Carbon–Carbon Bond
作者:Yoshihiro Nishimoto、Makoto Yasuda、Fei Wang、Junyi Yi
DOI:10.1055/a-1523-1551
日期:2021.11
Homologation of alkyl acetates, alkyl ethers, acetals, and ketals was accomplished via formal insertion of diazo esters into carbon–carbon σ-bonds. The combined Lewis acid InI3 with Me3SiBr catalyzed the homologation of alkyl acetates and alkyl ethers. That of acetals and ketals was catalyzed solely by the use of InBr3. The key point of the homologation mechanism is that the indium-based Lewis acids
Triaryl-substituted pyrrolo-p-phenylene-linked porphyrin-fullerene dyads: Expanding the structural diversity of photoactive materials
作者:Artem A. Strelnikov、Dmitriy V. Androsov、Alexander S. Konev、Daniil A. Lukyanov、Alexander F. Khlebnikov、Alexey V. Povolotskiy、Kaoru Yamanouchi
DOI:10.1016/j.tet.2018.04.084
日期:2018.6
A protocol for the synthesis of pyrrolo-p-phenylene-linked porphyrin-fullerene dyads suitable as photoactive materials was developed. The sequence of aziridination – aziridine ring opening – 1,3-dipolar cycloaddition reactions enabled us to provide structural variability both to the porphyrin core and to pyrrole linker, which facilitates designing the electronic structure and morphological parameters
A highly enantioselective 1,3-dipolarcycloaddition of α-substituted diazoesters with exocyclic enones was achieved with chiral scandium(III)/N, N’-dioxide complex as the catalyst. This protocol provided a facile and efficient route to optically active 1-pyrazoline-based spirochromanones and others with good outcomes (up to 97% yield, 98% ee with >95:5 dr). Moreover, enantioenriched 2-pyrazoline-based
correlated to the initial feed ratios of monomer to catalyst, confirming the living/controlled manner of the polymerizations. The Mn also increased linearly with the monomer conversion, and all of the isolated polymers showed narrow Mw/ Mns. The polymerization was relatively fast and could be accomplished within several minutes. Such fast livingpolymerization method can be applied to a wide range of diazoacetate