Progresses of Ring Expansion Reaction of Small Transitional Metallacyclic Compounds

过渡金属杂环化合物特别是过渡金属杂小环化合物(成环原子数小于6)在金属有机化学和配位化学领域中具有重要的地位,它们是许多过渡金属催化反应包括烯烃复分解反应、炔烃聚合反应的中间体.通常过渡金属杂小环化合物具有较大的环张力,因此极易与不饱和化合物反应生成环张力较小的扩环产物.针对过渡金属杂小环化学研究现状,综述了几类典型的过渡金属杂三、四、五元环的扩环反应.Metallacycles, especially those small rings, play an important role in the field of organometallic and coordination chemistry.They are considered as reactive intermediates in metal promoted or catalyzed reactions including olefin metathesis reactions and alkyne polymerization reactions.Due to the high ring strain, small metallacycles can easily react with unsaturated compounds to produce ring expansion products with lower ring strain.To further understand the importance of small metallacycle intermediates in the catalytic reactions and synthesis methodology, the ring expansion reactions of several typical three-, four- and five-membered metallacycles is summarize.国家自然科学基金(No.21272193); 福建省自然科学基金(No.2011J05031)资助项目~

Constraint of a ruthenium-carbon triple bond to a five-membered ring

含过渡金属碳三键(M≡C)的金属卡拜化合物是许多有机反应的催化剂或关键中间体。对其合成及性质的研究是金属有机化学的热点之一。由于卡拜碳的sp杂化方式，大部分金属卡拜化合物均为链状结构（卡拜碳键角理想值为180 °），环内金属卡拜化合物因存在很大的环张力而难于合成。夏海平教授课题组发展了由链状多炔（称之为碳龙）构筑碳龙配合物的高效方法（Nature Communications, 2017, 8, 1912），实现了锇杂戊搭炔/烯及其衍生物的一锅法合成。现在，他们把该方法进一步拓展到了第二过渡系金属钌，通过碳龙与市售的RuCl2(PPh3)3反应一锅合成了钌杂戊搭炔I。本研究是碳龙化学的进一步延伸和发展，首次把碳龙化学的金属中心由锇拓展到了其它金属，展示了碳龙化学广阔的发展空间。该研究工作在夏海平教授指导下完成，能源材料化学协同创新中心（iChEM）博士后卓庆德和张弘副教授为共同第一作者。iChEM博士后周小茜、博士生陈志昕、林剑锋、卓凯玥、硕士康慧君、林鑫磊参与了部分实验工作。博士生华煜晖负责理论计算。【Abstract】The incorporation of a metal-carbon triple bond into a ring system is challenging because of the linear nature of triple bonds. To date, the synthesis of these complexes has been limited to those containing third-row transition metal centers, namely, osmium and rhenium. We report the synthesis and full characterization of the first cyclic metal carbyne complex with a second-row transition metal center, ruthenapentalyne. It shows a bond angle of 130.2(3)° around the sp-hybridized carbyne carbon, which represents the recorded smallest angle of second-row transition metal carbyne complexes, as it deviates nearly 50° from the original angle (180°). Density functional theory calculations suggest that the inherent aromatic nature of these metallacycles with bent Ru≡C–C moieties enhances their stability. Reactivity studies showed striking observations, such as ambiphilic reactivity, a metal-carbon triple bond shift, and a [2 + 2] cycloaddition reaction with alkyne and cascade cyclization reactions with ambident nucleophiles.This research was supported by the National Key R&D Program of China (2017YFA0204902) and the National Natural Science Foundation of China (nos. 21490573,21332002, and 21561162001). 研究工作得到国家自然科学基金项目（21490573、21332002 和21561162001）和国家重点研发计划（2017YFA0204902）的资助

Successive modification of polydentate complexes gives access to planar carbon-and nitrogen-based ligands

以碳和氮为键合原子的多齿螯合物是配合物家族中非常重要的一类。具有更高齿数的平面构型NC螯合物实例相对较少，代表性的例子为四齿金属碳卟啉类化合物，这类螯合物以其独特的结构和丰富的物理化学性质引起广泛关注。然而平面五齿、六齿的NC螯合物由于几何构型“拥挤”导致合成难度高，该工作从含三元环内金属卡宾结构的CCCC型碳龙配合物出发，利用经典有机反应（炔烃对金属卡宾的插入反应），成功地实现了CCCCN/NCCCN型平面五齿螯合物的合成。这一研究为高配位型螯合物的合成提供了新思路并为平面五齿螯合物家族添加新成员。特别是，这些高配位型螯合物在可见光和近红外区域均有较好的吸收，表现出良好的光声成像、光热转换及声动力学性能。 该研究工作在张弘教授指导下完成，第一作者为iChEM博士后周小茜。该工作充分体现了多学科协同研究优势：相关化合物的合成、表征及理论计算工作由周小茜博士完成；声动力学性能研究由厦门大学公共卫生学院庞鑫博士及刘刚教授完成；光声成像研究由厦门大学公共卫生学院聂立铭教授完成。iChEM fellow卓庆德博士、博士生卓凯玥、陈志昕参与了部分实验工作。夏海平教授、香港科技大学林振阳教授和南京大学朱从青教授对研究工作给予了大力支持。【Abstract】Polydentate complexes containing combinations of nitrogen and carbon (N and C) ligating atoms are among the most fundamental and ubiquitous molecules in coordination chemistry, yet the formation of such complexes with planar high-coordinate N/C sites remains challenging. Herein, we demonstrate an efficient route to access related complexes with tetradentate CCCN and pentadentate CCCCN and NCCCN cores by successive modification of the coordinating atoms in complexes with a CCCC core. Combined experimental and computational studies reveal that the rich reactivity of metal-carbon bonds and the inherent aromaticity of the metallacyclic skeletons play key roles in these transformations. This strategy addresses the paucity of synthetic approaches to mixed N/C planar pentadentate chelating species and provides valuable insights into the synthesis of carbon-based high-coordinate complexes. Furthermore, the resulting complexes are the examples of organometallic species with combined photoacoustic, photothermal, and sonodynamic properties, which makes them promising for application in related areas.This research was supported by the National Natural Science Foundation of China (Nos. 21572185, 21561162001, and 81571744), the Research Grants Council of Hong Kong (N_HKUST603/15), the Excellent Youth Foundation of Fujian Scientific Committee (2018J06024), and the Fundamental Research Funds for the Central Universities (20720170065).该工作得到国家自然科学基金委、香港研究资助局、福建省自然科学基金、厦门大学校长基金的资助

Stabilization of anti-aromatic and strained five-membered rings with a transition metal

1981年诺贝尔化学奖获得者、美国康奈尔大学RoaldHoffmann教授评价该项工作说：'The　paper is an excellent one--it's　quite a mazing that the parent Os　system,molecule 1,chooses to give the osmapentalyne'。德国化学家Uwe Rosenthal教授等在同期《自然—化学》杂志的《News and Views》栏目以《Breaking the rules》为题撰文评述了这一研究成果。全文地址：http://www.nature.com/nchem/journal/vaop/ncurrent/pdf/nchem.1702.pdfAnti-aromatic compounds, as well as small cyclic alkynes or carbynes, are particularly challenging synthetic goals. The combination of their destabilizing features hinders attempts to prepare molecules such as pentalyne, an 8π-electron anti-aromatic bicycle with extremely high ring strain. Here we describe the facile synthesis of osmapentalyne derivatives that are thermally viable, despite containing the smallest angles observed so far at a carbyne carbon. The compounds are characterized using X-ray crystallography, and their computed energies and magnetic properties reveal aromatic character. Hence, the incorporation of the osmium centre not only reduces the ring strain of the parent pentalyne, but also converts its Hückel anti-aromaticity into Craig-type Möbius aromaticity in the metallapentalynes. The concept of aromaticity is thus extended to five-membered rings containing a metal–carbon triple bond. Moreover, these metal–aromatic compounds exhibit unusual optical effects such as near-infrared photoluminescence with particularly large Stokes shifts, long lifetimes and aggregation enhancement

Technology Design of Power Supply Services Integrated Platform

随着"互联网+"概念的兴起,供电服务迎来了新的机遇。未来的供电服务,将会利用物联网和互联网并融合先进技术如大数据等,打破现阶段各系统各部门之间的壁垒,实现下到用户终端、上到电力生产的全产业链信息的互联互通;利用云计算技术,搭建电力行业云效力平台,提供跨系统、跨平台、跨地域的标准化一致性效力;利用大数据技术,对整个系统的数据信息进行综合分析计算,为供电服务提供高智能、高效率的决策结果,形成"互联网+"下的新型供电服务形态。本文搭建售电效力平台技术框架。根据售电侧开放环境下新型供电业务变化和管理需求,确定新型供电业务模式。根据现有供电相干业务系统建设及应用情况,确定新型供电业务应用系统定位,规划现..

3-6岁幼儿言语表达能力发展特点研究

本研究采用口语表述和运作表达两个实验探讨了 3— 6岁幼儿言语表达能力的发展特点。结果表明 :幼儿口语表达和动作表现能力随年龄增长逐渐提高 ,3— 5岁是幼儿口语表述能力发展的快速期。口语表述内容由可视的、外在的特征逐渐转向内在特征 ,呈现由固有属性向关系属性发展的趋势。幼儿期动作表达特点以发展核心动作并进行扩展为主。 4岁是动作表达的转折时期。 4岁和 5岁是两种表达方式关系发展最密切的时期

A RESEARCH ON THE DEVELOPMENTAL CHARACTERISTICS OF YOUNG CHILDRENS LANGUAGE EXPRESSION

本研究采用口语表述和运作表达两个实验探讨了 3— 6岁幼儿言语表达能力的发展特点。结果表明 :幼儿口语表达和动作表现能力随年龄增长逐渐提高 ,3— 5岁是幼儿口语表述能力发展的快速期。口语表述内容由可视的、外在的特征逐渐转向内在特征 ,呈现由固有属性向关系属性发展的趋势。幼儿期动作表达特点以发展核心动作并进行扩展为主。 4岁是动作表达的转折时期。 4岁和 5岁是两种表达方式关系发展最密切的时期

A RESEARCH ON THE DEVELOPMENTAL CHARACTERISTICS OF YOUNG CHILDRENS LANGUAGE EXPRESSION

本研究采用口语表述和运作表达两个实验探讨了 3— 6岁幼儿言语表达能力的发展特点。结果表明 :幼儿口语表达和动作表现能力随年龄增长逐渐提高 ,3— 5岁是幼儿口语表述能力发展的快速期。口语表述内容由可视的、外在的特征逐渐转向内在特征 ,呈现由固有属性向关系属性发展的趋势。幼儿期动作表达特点以发展核心动作并进行扩展为主。 4岁是动作表达的转折时期。 4岁和 5岁是两种表达方式关系发展最密切的时期