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Walking Cations: Transition-Metal Free Benzyl Cation-Triggered sp^(2) C—H Phosphorylation and Etherification

Chinese Journal of Chemistry 2022年第24期40卷 2933-2938页

作者： Kuan Liu Bin Song Qi Dang Long Liu Jie Tang Tianzeng Huang Chunya Li Zhi Tang Tieqiao Chen Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources Hainan Provincial Key Lab of Fine ChemHainan Provincial Fine Chemical Engineering Research CenterHainan UniversityHaikouHainan570228 China

A novel benzyl cation-triggered site-selective sp^(2) C—H phosphorylation and etherification was developed. This reaction was conducted under the transition metal-free conditions through cation migration via dearomatization. Under the reaction conditions, the derivatives of naphthalenes, benzofurans and benzo[b]thiophenes all can be transformed into the corresponding products in good to excellent yields. It provides a method to construct sp^(2) C—P and sp^(2) C—O bonds as well as a new strategy for benzylic activation-triggered sp^(2) C—H functionalization.

关键词： Transition metal-free Cation migration site-selectivity Phosphorylation Etherification

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Recent Advances in Asymmetric Transformations of Unactivated Alkanes and Cycloalkanes through Direct C—H Functionalization

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Chinese Journal of Chemistry 2022年第23期40卷 2825-2837,I0002页

作者： Shiyan Cheng Qianyu Li Xiuliang Cheng Yu-Mei Lin Lei Gong Key Laboratoryof Chemical Biology of Fujian Province Collegeof Chemistry and Chemical EngineeringXiamen UniversityXiamen Fujian 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) XiamenFujian 361005China

The direct conversion of unactivated alkanes and cycloalkanes into structurally diverse molecules through aliphatic C—H functionalization is a useful process, which has attracted intense interest from academia and industry. Methods to control chemo- and site-selectivity, combined with asymmetric catalysis, provide appealing access to high value-added enantiomer-enriched compounds but are far less developed. This review focuses on recent progress in (i) asymmetric reactions of alkanes or cycloalkanes with prochiral substrates which generate a stereocenter adjacent to the cleaved C(sp3)–H bond, and (ii) C(sp3)–H enantiodiscriminatory reactions creating a new stereogenic center on the carbon of a cleaved C(sp3)–H bond. Elegant strategies are discussed, including (a) metal carbene-induced C—H insertions by chiral rhodium catalysts, (b) metal-oxo-mediated C—H oxidation by biomimetic manganese catalysts, (c) enzyme catalysis by cytochromes P450 variants, and (d) dual catalysis by a photocatalyst and a chiral Lewis acid (CLA) or a chiral phosphoric acid (CPA). These catalytic systems can not only precisely recognize primary, secondary and tertiary C—H bonds at specific positions in alkanes and cycloalkanes, but also support a high level of stereoselectivity in the reactions. It is expected that the advances will stimulate further progress in asymmetric catalysis, synthetic methodology, pharmaceutical development and industrial processes.

关键词： Asymmetric catalysis C-H functionalization Alkane site-selectivity Enantioselectivity

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site selective 5f electronic correlations inβ-uranium

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Chinese Physics B 2023年第1期32卷 421-426页

作者：邱睿智谢刘桦黄理 Institute of Materials China Academy of Engineering PhysicsMianyang 621907China School of Physical Science and Technology Southwest UniversityChongqing 400715China Science and Technology on Surface Physics and Chemistry Laboratory Mianyang 621908China

We investigate the electronic structure ofβ-uranium,which has five nonequivalent atomic sites in its unit cell,by means of the density functional theory plus Hubbard-U correction with U from linear response calculation.It is found that the 5f electronic correlations inβ-uranium are moderate.More interestingly,their strengths are site selective,depending on the local atomic environment of the present uranium atom.As a consequence,the occupation matrices and partial 5f density of states ofβ-uranium manifest site dependence.In addition,the complicate experimental structure ofβ-uranium could be well reproduced within this theoretical framework.

关键词： uranium low-symmetry crystal structure 5f electronic correlation site-selectivity density-functional theory

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高化学选择性和区域选择性的苯酚碳氢键官能化（英文）

高化学选择性和区域选择性的苯酚碳氢键官能化（英文）

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第十九届全国金属有机化学学术讨论会

作者：刘路张俊良华东师范大学化学与分子工程学院

In last few years,gold revealed more and more unique properties in carbene chemistry.1]Last year,we disclosed that the gold carbenes have an unprecedented chemo-and site-selectivity and ligand effect toward

关键词： C-H functionalization diazo compounds chemo-selectivity site-selectivity phenols

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