1456693-84-7Relevant academic research and scientific papers
Copper-catalyzed aerobic double functionalization of benzylic C(sp3)-H bonds for the synthesis of 3-hydroxyisoindolinones
Nozawa-Kumada, Kanako,Matsuzawa, Yuta,Ono, Kanako,Shigeno, Masanori,Kondo, Yoshinori
supporting information, p. 8604 - 8607 (2021/09/02)
A copper-catalyzed aerobic 3-hydroxyisoindolinone synthesis was developed via the benzylic double C(sp3)-H functionalization of 2-alkylbenzamides. In this reaction, molecular oxygen was used as both an oxidant for C(sp3)-H functionalization and an oxygen source. Our method can be extended to diverse benzylic C(sp3)-H bonds and shows excellent functional group tolerance. This journal is
Testing the limits of radical-anionic CH-amination: A 10-million-fold decrease in basicity opens a new path to hydroxyisoindolines via a mixed C-N/C-O-forming cascade
Alabugin, Igor V.,Dos Passos Gomes, Gabriel,Elliott, Quintin,Evoniuk, Christopher J.
, p. 6539 - 6555 (2020/07/15)
An intramolecular C(sp3)-H amidation proceeds in the presence of t-BuOK, molecular oxygen, and DMF. This transformation is initiated by the deprotonation of an acidic N-H bond and selective radical activation of a benzylic C-H bond towards hydrogen atom transfer (HAT). Cyclization of this radical-anion intermediate en route to a two-centered/three-electron (2c,3e) C-N bond removes electron density from nitrogen. As this electronegative element resists such an oxidation , making nitrogen more electron rich is key to overcoming this problem. This work dramatically expands the range of N-anions that can participate in this process by using amides instead of anilines. The resulting 107-fold decrease in the N-component basicity (and nucleophilicity) doubles the activation barrier for C-N bond formation and makes this process nearly thermoneutral. Remarkably, this reaction also converts a weak reductant into a much stronger reductant. Such reductant upconversion allows mild oxidants like molecular oxygen to complete the first part of the cascade. In contrast, the second stage of NH/CH activation forms a highly stabilized radical-anion intermediate incapable of undergoing electron transfer to oxygen. Because the oxidation is unfavored, an alternative reaction path opens via coupling between the radical anion intermediate and either superoxide or hydroperoxide radical. The hydroperoxide intermediate transforms into the final hydroxyisoindoline products under basic conditions. The use of TEMPO as an additive was found to activate less reactive amides. The combination of experimental and computational data outlines a conceptually new mechanism for conversion of unprotected amides into hydroxyisoindolines proceeding as a sequence of C-H amidation and C-H oxidation.
Recyclable cellulose-palladium nanoparticles for clean cross-coupling chemistry
Lu, Zhichao,Jasinski, Jacek B.,Handa, Sachin,Hammond, Gerald B.
supporting information, p. 2748 - 2752 (2018/04/27)
Cheap, recyclable, and robust cellulose-palladium nanoparticles were developed and fully characterized by FTIR, TEM, XPS, TGA, and NMR. The nanoparticles enabled cross-coupling chemistry in a truly general fashion i.e., Suzuki-Miyaura, Heck, Sonogashira, and C-H activation. Notably, all types of transformations were achieved with a single type of nanocatalyst. Complete recyclability of the catalyst and low traces of palladium in the product demonstrates the greenness of the protocol.
Eosin Y as a Redox Catalyst and Photosensitizer for Sequential Benzylic C?H Amination and Oxidation
Yan, Dong-Mei,Zhao, Quan-Qing,Rao, Li,Chen, Jia-Rong,Xiao, Wen-Jing
supporting information, p. 16895 - 16901 (2018/10/26)
A new synergistic multicatalytic activation mode of eosin Y has been discovered by exploiting the redox potential of its ground state and excited state. This catalytic strategy proves to be an enabling tool for visible-light-driven sequential benzylic C?H amination and oxidation of o-benzyl-N-methoxyl-benzamides when using Selectfluor as a hydrogen atom transfer (HAT) reagent and O2 as oxidant. Efficient synthesis of a range of diversely functionalized 3-hydroxyisoindolinones can thus be achieved with good yields and selectivity at mild reaction conditions. Preliminary mechanistic studies and DFT calculations suggest that eosin Y works as a redox catalyst and photosensitizer.
Efficient synthesis of hydroxyl isoindolones by a Pd-mediated C-H activation/annulation reaction
Yu, Qingzhen,Zhang, Nana,Huang, Jianhui,Lu, Shaonan,Zhu, Yi,Yu, Xiaoxiao,Zhao, Kang
supporting information, p. 11184 - 11188 (2013/09/02)
Radical reaction: A convenient synthesis of hydroxyl isoindolones by a Pd-catalyzed C-H activation/annulation reaction with near "click chemistry" efficiency is presented (see scheme; TBHP=tert-butyl hydrogen peroxide). This methodology features short reaction times (10-30 min), high atom economy, wide substrate scope (22 examples), and good reaction yields (up to 93 %). Copyright
