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The regulatory mechanism of rapid lignification for timely anther dehiscence

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Journal of Integrative Plant Biology 2024年第8期66卷 1788-1800页

作者： Jing-Shi Xue Yi-feng feng Ming-Qi Zhang Qin-Lin Xu Ya-Min Xu Jun-Qin Shi Li-Fang Liu xiao-feng wu Shui Wang Zhong-Nan Yang Shanghai Key Laboratory of Plant Molecular Sciences College of Life SciencesShanghai Normal UniversityShanghai 200234China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China University of the Chinese Academy of Sciences Beijing 100049China Development Center of Plant Germplasm Resources College of Life SciencesShanghai Normal UniversityShanghai 200234China

Anther dehiscence is a crucial event in plant reproduction,tightly regulated and dependent on the lignification of the anther *** this study,we investigated the rapid lignification process that ensures timely anther dehiscence in *** findings reveal that endothecium lignification can be divided into two distinct *** Phase Ⅰ,lignin precursors are synthesized without polymerization,while Phase Ⅱ involves simultaneous synthesis of lignin precursors and *** transcription factors MYB26,NST1/2,and ARF17 specifically regulate the pathway responsible for the synthesis and polymerization of lignin monomers in Phase Ⅱ.MYB26-NST1/2 is the key regulatory pathway responsible for endothecium lignification,while ARF17 facilitates this process by interacting with ***,our results demonstrate that the lignification of the endothecium,which occurs within approximately 26 h,is much faster than that of the vascular *** findings provide valuable insights into the regulation mechanism of rapid lignification in the endothecium,which enables timely anther dehiscence and successful pollen release during plant reproduction.

关键词： anther dehiscence ARF17 endothecium lignin MYB26 NST

Generation and transformation ofα-oxy carbene intermediates enabled by copper-catalyzed carbonylation

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Green Carbon 2024年第1期2卷 70-80页

作者： Yang Yuan xiao-feng wu Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of Sciences116023 DalianLiaoningChina Leibniz-Institut für Katalyse e.V. Albert-Einstein-Straße 29a18059 RostockGermany

Since the Fischer-Tropsch reaction was discovered by Otto Roelen in 1938,transition metal-catalyzed carbo-nylation reactions come in as one of the most important methods for preparing carbonyl-containing and carbon chain-increased *** a result,the field of carbonylation research has received considerable attention over the past decades and continues to *** the continuous development of carbonylation and the in-depth study of the mechanism,more mechanistic details and variations have been revealed,which provide more possibilities for organic ***,copper catalysis has been introduced to the carbonylative functio-nalization of alkenes,thus enabling the rapid assembly of functionalized carbonyl compounds from simple starting *** this Account,we summarize the new findings in the Cu-catalyzed borocarbonylation of alkenes based on the generation and transformation ofα-oxy carbene *** believe that the results presented in this Account will further inspire the design of new carbonylation reactions.

关键词： Carbonylation Copper catalyst Carbene Carbon monoxide Domino reaction

Palladium-catalyzed oxidative double alkoxycarbonylation of ethylene toward succinic acid derivatives

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Green Carbon 2024年第2期2卷 205-208页

作者： Zhi-Peng Bao Cunyao Li Li Yan Yunjie Ding xiao-feng wu Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning 116023China Leibniz-Institut für Katalyse e.V. Rostock 18059Germany

Employing biodegradable plastics is one of the choices to solve white pollution *** succinate(PBS),as a biodegradable plastic with good stability and heat resistance,is produced by polymerization of succinic acid and butylene ***,inadequate supply of the direct upstream material succinic acid restricts the development of this *** this work,we provide a carbonylative strategy to construct succinic acid derivatives from carbon monoxide(CO),ethylene and *** reaction catalyzed by palladium catalyst under oxidative conditions.

关键词： Ethylene Alcohols Palladium Carbonylation Succinic acid derivatives

钯催化羰基化合成α-三氟甲基取代酮和羧酸衍生物

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Chinese Journal of Catalysis 2024年第5期60卷 171-177页

作者：包志鹏孙乃先吴小锋中国科学院大连化学物理研究所大连洁净能源国家实验室辽宁大连116023 莱布尼茨催化研究所德国罗斯托克南京工业大学生物技术与制药工程学院江苏南京211816

α-三氟甲基取代的有机化合物在制药和材料领域有着广泛的应用,因而其合成引起了有机化学研究者的广泛关注.然而,构建这类化合物的方法相对有限.在众多α-三氟甲基取代的有机物中,α-三氟甲基取代的羧酸衍生物因其特殊性而备受关注.许... 详细信息

α-三氟甲基取代的有机化合物在制药和材料领域有着广泛的应用,因而其合成引起了有机化学研究者的广泛关注.然而,构建这类化合物的方法相对有限.在众多α-三氟甲基取代的有机物中,α-三氟甲基取代的羧酸衍生物因其特殊性而备受关注.许多商业化药物的活性成分都含有这种基团.在制备这类化合物时,研究者们通常选择含羰基类化合物和三氟甲基源作为原料.虽然这种方法在合成过程中展现了一定的优势,但也存在一些明显的缺点,其中最为突出的是原料的稳定性和易得性问题,因此发展新的合成策略非常重要.羰基化反应是制备含羰基类化合物的一种直接且有效的方法.然而,目前大多数羰基化反应主要集中在使用芳基类底物上,而对于烷基类底物,由于其键能相对较高,因此在实际应用中受到了较多的限制.本文利用Csp3-X键能高的特点,通过钯催化活化及自由基中间体的作用,成功实现了α-三氟甲基取代酮和羧酸衍生物的高效合成.在标准反应条件下,苯酚类和醇类化合物均可作为反应底物转化制得相应的酯类化合物.当使用亲核性更强的芳基胺或烷基胺作为底物时,也可以高效制备出酰胺类目标产物.值得一提的是,即使采用亲核性较低的磺酰胺和酰胺作为反应底物,也能以较高的收率得到对应的酰亚胺类化合物.此外,当使用更具挑战性的碳亲核试剂——芳基硼酸类化合物时,该反应仍能实现中等以上的收率,得到目标产物α-三氟甲基取代酮.总体而言,该反应具有良好的底物官能团兼容性,可以高收率制得酰胺类、酯类、酮类和酰亚胺类化合物.此外,该策略可以在较低的一氧化碳压力下实现该转化的放大反应,并且适用于25种具有密集官能团的药物和天然产物的后期修饰.实验发现,对于不同亲核试剂的竞争反应,苯酚的反应速度大约是苯胺的2倍.此外,通过自由基抑制剂、捕获剂等实验证实了反应过程中存在自由基.因此,在反应机理方面,我们认为三氟碘乙烷和零价钯的反应经历了单电子的碳自由基中间体过程,最终形成了二价钯配合物中间体,从而完成了后续反应.综上,本文开发了一种钯催化羰基化合成α-三氟甲基取代酮和羧酸衍生物的方法,可用于复杂含α-三氟甲基类化合物的制备.该反应策略可以应用于天然产物的修饰、新型药物的研发等领域,也为烷基卤代物的羰基化转化提供了新思路.

关键词： α-三氟甲基取代酰胺酯酮酰亚胺羰基化

Microstructure and dry sliding wear behavior of cast Al-Mg_2Si in-situ metal matrix composite modified by Nd

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Rare Metals 2013年第3期32卷 284-289页

作者： xiao-feng wu Guan-Gan Zhang Fu-Fa wu School of Materials Science and Engineering Liaoning University of Technology

The microstructure and dry sliding wear behav- ior of cast Al-18 wt% MgaSi in-situ metal matrix com- posite modified by Nd were investigated. Experimental results show that, after introducing a proper amount of Nd, both primary and eutectic Mg2Si in the Al-18 wt% Mg2Si composite are well modified. The morphology of primary Mg2Si is changed from irregular or dendritic to polyhedral shape, and its average particle size is signifi- cantly decreased. Moreover, the morphology of the eutectic MgzSi phase is altered from flake-like to very short fibrous or dot-like. The wear rates and friction coefficient of the composites with Nd are lower than those without Nd. Furthermore, the addition of 0.5 wt% Nd changes the wear mechanism of the composite from the combination of abrasive, adhesive, and delamination wear without Nd into a single mild abrasion wear with 0.5 wt% Nd.

关键词： Al/Mg2Si composites Nd modification Microstructure Dry sliding wear behavior

Cu/Pd-catalyzed borocarbonylative trifunctionalization of alkynes and allenes:synthesis ofβ-geminal-diboryl ketones

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Science China Chemistry 2021年第12期64卷 2142-2153页

作者： Yang Yuan Fu-Peng wu Anke Spannenberg xiao-feng wu Leibniz-Institut für Katalyse e.V.an der Universität Rostock Albert-Einstein-Straβe 29a18059RostockGermany Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China

Functionalized bisboryl compounds have recently emerged as a new class of synthetically useful building blocks in organic ***,we report an efficient strategy to synthesizeβ-geminal-diboryl ketones enabled by a Cu/Pd-catalyzed borocarbonylative trifunctionalization of readily available alkynes and *** reaction promises to be a useful method for the synthesis of functionalizedβ-geminal-diboryl ketones with broad functional group *** studies suggest that the reaction proceeds through borocarbonylation/hydroboration cascade of both alkynes and allenes.

关键词： carbonylation copper/palladium alkynes/allenes trifunctionalization β-geminal-diboryl ketones

Palladium-catalysed efficient synthesis of primary alkyl halides from terminal and internal alkenes

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National Science Review 2022年第12期9卷 63-65页

作者： Han-Jun Ai Matthias Beller xiao-feng wu Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences Leibniz-Institut für Katalyse e.V.

The development of remote functionalization of alkenes has recently gained considerable attention as it offers the op-portunity to directly transform a mixture of unrefined olefin isomers into a single valuable fine c...

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Radical Carbonylation under Low CO Pressure:Synthesis of Esters from Activated Alkylamines at Transition Metal-Free Conditions

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Chinese Journal of Chemistry 2021年第4期39卷 927-932页

作者： fengqian Zhao Han-Jun Ai xiao-feng wu Leibniz-Institut fur Katalyse e.V.an der Universitat Rostock Albert-Einstein-Straße 29a18059 RostockGermany Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning116023 China

Main observation and conclusion High CO pressure(>40 bar)is usually needed in radical carbonylation reactions in the absence of metal *** this communication,we developed a transition-metal-free radical carbonylation of activated alkylamines with phenols and alcohols under low CO pressure(1-6 bar).Various esters were obtained in moderate to excellent yields under simple reaction conditions with good functional group compatibility.

关键词： Carbonylation Radical Ester Alkylamine Katritzky salt

C–F bond activation under transition-metal-free conditions

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Science China Chemistry 2021年第10期64卷 1630-1659页

作者： Han-Jun Ai Xingxing Ma Qiuling Song xiao-feng wu Leibniz-Institut fur Katalyse e.V.an der Universitat Rostock Rostock 18059Germany Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Key Laboratory of Molecule Synthesis and Function Discovery Fujian Province UniversityCollege of ChemistryFuzhou UniversityFuzhou 350108China Institute of Next Generation Matter Transformation College of Material Sciences&EngineeringHuaqiao UniversityXiamen 361021China

The unique properties of fluorine-containing organic compounds make fluorine substitution attractive for the development of pharmaceuticals and various specialty materials,which have inspired the evolution of diverse C–F bond activation *** many advances have been made in functionalizations of activated C–F bonds utilizing transition metal complexes,there are fewer approaches available for nonactivated C–F bonds due to the difficulty in oxidative addition of transition metals to the inert C–F *** this regard,using Lewis acid to abstract the fluoride and light/radical initiator to generate the radical intermediate have emerged as powerful tools for activating those inert C–F ***,these transition-metal-free processes are greener,economical,and for the pharmaceutical industry,without heavy metal *** review provides an overview of recent C–F bond activations and functionalizations under transition-metal-free *** key mechanisms involved are demonstrated and discussed in ***,a brief discussion on the existing limitations of this field and our perspective are presented.

关键词： transition-metal-free fluorinated compounds C–F activation coupling