McMurry coupling

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Running Coupling in SU(3) Yang-Mills Theory

cal running coupling constant at small separation r. This requires control of the force from short to long distance in one simulation with a r L holding for the whole range of physical r involved. With L=a always limited to feasible lattice sizes like 32 or 48, compromises on the above conditions have to be accepted, and it is hardly possible to vary all scale ratios signi cantly to check for the stability of the results. State of the art calculations along these lines are reported in 1,2]. It has to be noted that the highest physical energies r 1 that can be reached here are below about 2 GeV, if one only stays a factor 2 : : : 3 away from the cuto energy. Cuto e ects are corrected semi-empirically using the lattice Coulomb propagator. While these are di cult and careful simulations, we nd it somewhat hard to assess the systematic errors in a completely convincing fashion. An alternative attempt to derive the coupling in QCD has been pioneered by the Fermilab group 3]. Here, in a quenched simulation, the spin averaged 1P-1S charmonium splitting is determined on a physically large lattice. Although this is a nice experimentally known scale with little sensitivity to the quark masses, also other masses could in principle be used here to set the scale. The point relevant in the present context is, that they extract from such a simulation the bare lattice coupling g0 together with the corresponding lattice spacing a in GeV. A perturbative method is then used to relate g0 to a physical coupling at a scale of the order of the cuto . The scale problem is clearly alleviated in comparison to the quark force method, as e ectively the cuto a 1 is identi ed with the high energy physical scale.

北师大考博辅导班：2019北京师范大学有机化学考博难度解析及经验分享

北师大考博辅导班：2019北京师范大学有机化学考博难度解析及经验分享根据教育部学位与研究生教育发展中心最新公布的第四轮学科评估结果可知，在2018-2019年有机化学专业学校排名中，排名第一的是南开大学，排名第二的是北京大学，排名第三的是浙江大学。

下面是启道考博辅导班整理的关于北京师范大学有机化学考博相关内容。

一、专业介绍有机化学专业是一级学科化学下设的二级学科以天然有机产物和生物活性分子、金属与元素有机化合物为主要研究对象，从研究有机合成化学和物理有机化学着手，发展有机化学的反应、合成、方法和理论。

依据研究生教育要"面向现代化、面向世界、面向未来"的要求，培养德、智、体全面发展的现代化建设所需要的有机化学专业的专门人才。

该专业毕业生可到中等以上的学校做化学教师化学教学研究人员及其他教育工作者。

亦可到生产企业从事相关的研究和应用工作，比如一些大型制药公司，检验检疫局类的单位。

北京师范大学化学学院的有机化学专业在博士招生方面，划分为8个研究方向：070303有机化学研究方向：01金属有机化学02化学生物学,生物有机化学,有机分子与核酸03超分子组装，超分子材料化学04仿生纳米结构的设计、合成及自组装研究05有机光功能材料06过渡金属催化与有机合成07有机合成化学08不对称催化考试科目：①1101英语②2008化学一③3188化学二二、考试内容（一）初审化学学院将由各专业学科方向专家组对考生提交的申请材料进行初审。

初审专家评审组由学生报考导师在内的3位以上的专家组成，各专业学科方向的负责人作为专家评审组长，根据学生邮寄的报名申请材料以及其发表的学术科研论文情况等作为审核依据，初审着重考查考生的学术背景、基础知识、研究经历、研究设想、创新能力等。

评审组填写《化学学院博士研究生审核录取初审情况表》，院系审核后，统一向考生发送复试通知。

按照不低于1:2的比例确定复试名单（本博生、硕博连读生均占用博士录取名额）。

人名反应——精选推荐

氧化还原：氧化：Baeyer-Villiger氧化酮过酸氧化成酯迁移规则：叔>仲>环己基>苄>伯>甲基>氢Corey-Kim 氧化醇在NCS/DMF作用后，碱处理氧化成醛酮Criegee邻二醇裂解邻二醇由Pb（OAc）4氧化成羰基化合物Criegee臭氧化烯烃臭氧化后水解成醛酮Dakin反应对羟基苯甲醛由碱性H2O2氧化成对二酚Dess－Martin过碘酸酯氧化仲醇由过碘酸酯氧化成酮Fleming氧化硅烷经过酸化，过酸盐氧化，水解以后形成醇Hooker氧化2－羟基－3烷基－1，4－醌被KMnO4氧化导致侧链烷基失去一个亚甲基，同时羟基和烷基位置互变Moffatt氧化（Pfitzner－Moffatt）氧化用DCC和DMSO氧化醇，形成醛酮Oppenauer氧化烷氧基催化的仲醇氧化成醛酮Riley氧化活泼亚甲基（羰基α位等）被SeO2氧化成酮Rubottom氧化烯醇硅烷经过m－CPBA和K2CO3处理后α－羟基化Sarett氧化CrO3。

Py络合物氧化醇成醛酮Swern氧化用(COCl)2,DMSO为试剂合Et3N淬灭的方法将醇氧化成羰基化合物Tamao－Kumada氧化烷基氟硅烷被KF，H2O2，KHCO3氧化成醇Wacker氧化Pd催化剂下，烯烃氧化成酮还原：Barton－McCombie去氧反应从相关的硫羰基体中间用n－Bu3SnH，AIBN试剂经过自由基开裂发生醇的去氧作用Birch 还原苯环由Na单质合液胺条件下形成环内二烯烃带供电子基团的苯环：双键连接取代基带吸电子基团的苯环，取代基在烯丙位Brown硼氢化烯烃和硼烷加成产生的有机硼烷经过碱性H2O2氧化得到醇Cannizzaro歧化碱在芳香醛，甲醛或者其他无α－氢的脂肪氢之间发生氧化还原反应给出醇和酸Clemmensen还原用锌汞齐和氯化氢将醛酮还原为亚甲基化合物Corey－Bakshi－Shibata(CBS)还原酮在手性恶唑硼烷催化下的立体选择性还原Gribble吲哚还原用NaBH4直接还原会导致N－烷基化，NaBH3CN在冰醋酸当中还原吲哚双键可以解决Gribble二芳基酮还原用NaBH4在三氟乙酸中还原二芳基酮和二芳基甲醇为二芳基甲烷，也可以应用于二杂芳环酮和醇的还原Luche还原烯酮在NaBH4－CeCl3下发生1，2－还原形成烯丙位取代烯醇McFadyen－Stevens还原酰基苯磺酰肼用碱处理成醛Meerwein－Ponndorf－Verley还原用Al（OPr’）3/Pr’OH体系将酮还原为醇Midland还原用B－3－α－蒎烯－9－BBN对酮进行不对称还原Noyori不对称氢化羰基在Ru（II）BINAP络合物催化下发生不对称氢化还原Rosenmund还原用BaSO4/毒化Pd催化剂将酰氯氢化成醛，如催化剂未被毒化，会氢化为醇Wolff－Kishner－黄鸣龙还原用碱性肼将羰基还原为亚甲基成烯反应:Boord反应β-卤代烷氧基与Zn作用生成烯烃Chugaev消除黄原酸酯热消除成烯Cope消除胺的氧化物热消除成烯烃Corey-Winter olefin烯烃合成邻二醇经1,1-硫代羰基二咪唑和三甲氧基膦处理转化为相应的烯Doering-LaFlamme丙二烯合成烯烃用溴仿以及烷氧化物处理以后生成同碳二溴环丙烷再反应生成丙二烯Horner-Wadsworth-Emmons反应从醛合磷酸酯生成烯烃.副产物为水溶性磷酸盐,故以后处理较相应的Witting反应简单的多Julia-Lythgoe成烯反应从砜合醛生成(E)-烯烃Peterson成烯反应从α-硅基碳负离子合羰基化合物生成烯烃.也成为含硅的Witting反应Ramberg-Backlund烯烃合成Α-卤代砜用碱处理生成烯烃Witting反应羰基用膦叶立德变成烯烃Zaitsev消除E2消除带来更多取代的烯烃偶联反应：Cadiot-Chodkiewicz偶联从炔基卤和炔基酮合成双炔衍生物Castro－Stephens偶联芳基炔合成，同Cadiot-Chodkiewicz偶联Eglinton反应终端炔烃在化学计量（常常过量）Cu(Oac)2促进下发生的氧化偶联反应Eschenmoser偶联从硫酰胺和烷基卤生成烯胺Glaser偶联Cu催化终端炔烃的氧化自偶联Gomberg－Bachmann偶联碱促进下芳基重氮盐和一个芳烃之间经自由基偶联生成二芳基化合物Heck反应Pb催化的有机卤代物或者三氟磺酸酯和烯烃之间的偶联反应杂芳基Heck反应发生在杂芳基受体上的Pd(Ph3P)4,Ph3P,CuI,Cs2CO3催化下的分子内或者分子间Heck反应Hiyama交叉偶联反应Pb催化有机硅和有机卤代物或者三氟磺酸酯等在诸如F－或者OH－之类的活化剂Pd(Ph3P)4,TBAF催化剂存在下发生的交叉偶联反应Kumada交叉偶联（Kharasch交叉偶联）Ni和Pd催化下，格氏试剂和一个有机卤代物或者三氟磺酸酯之间的交叉偶联Liebeskind－Srogl偶联硫酸酯和有机硼酸之间经过Pd催化发生交叉偶联生成酮McMurry 偶联羰基用低价Ti，如TiCl3/LiAlH4产生的Ti(0)处理得到双键，反应是一个单电子过程Negishi交叉偶联Pd催化的有机Zn和有机卤代物，三氟磺酸酯等之间发生的交叉偶联反应Sonogashira反应Pd/Cu催化的有机卤和端基炔烃之间的交叉偶联反应Stille偶联Pd催化的有机Sn和有机卤，三氟磺酸酯之间的交叉偶联反应Stille－Kelly偶联双Sn试剂进行Pd催化下二芳基卤代物的分子交叉偶联Suzuki偶联Pd催化下的有机硼烷和有机卤，三氟磺酸酯在碱存在下发生的交叉偶联Ullmann反应芳基碘代物在Cu存在下的自偶联反应Wurtz反应烷基卤经Na或Mg金属处理后形成碳碳单键Ymada偶联试剂用二乙基氰基磷酸酯(EtO)2PO-CN活化羧酸缩合反应：Aldol缩合羰基和一个烯醇负离子或一个烯醇的缩合Blaise反应腈和α－卤代酯和Zn反应得到β－酮酯Benzoin 缩合芳香醛经CN－催化为安息香(二芳基乙醇酮)Buchner-Curtius-Schlotterbeck反应羰基化合物和脂肪族重氮化物反应给出同系化的酮Claisen缩合酯在碱催化下缩合为β－酮酯Corey-Fuchs反应醛发生一碳同系化生成二溴烯烃,然后用BuLi处理生成终端炔烃Darzen缩水甘油酸酯缩合碱催化下从α－卤代酯和羰基化合物生成α，β－环氧酯（缩水甘油醛）Dieckmann缩合分子内的Claisen缩合Evans aldol反应用Evans手性鳌合剂,即酰基恶唑酮进行不对称醇醛缩合Guareschi－Thorpe缩合（2－吡啶酮合成）氰基乙酸乙酯和乙酰乙酸在氨存在下生成2－吡啶酮Henry硝醇反应醛和有硝基烷烃在碱作用下去质子化产生氮酸酯Kharasch加成反应过渡金属催化的CXCl3对于烯烃的自由基加成Knoevenagel缩合羰基化合物和活泼亚甲基化合物在胺的催化下缩合Mannnich缩合（羰基胺甲基化）胺，甲醛，和一个带有酸性亚甲基成分的化合物之间的三组分反应发生胺甲基化Michael加成亲核碳原子对α,β-不饱和体系的共扼加成Mukaiyama醇醛缩合Lewis酸催化下的醛和硅基烯醇醚之间的Aldol缩合Nozaki－Hiyama－KIshi反应Cr－Ni双金属催化下的烯基卤对于醛的氧化还原加成Pechmann缩合（香豆素合成）Lewis酸促进的酸和β－酮酯缩合成为香豆素Perkin反应芳香醛和乙酐反应合成肉桂酸Prins反应烯烃酸性条件下对于甲醛的加成反应Reformatsky反应有机Zn试剂（从α－卤代酯来）对羰基的亲核加成反应Reimer－Tiemann反应从碱性介质当中从酚和氯仿合成邻甲酰基苯酚Schlosser对Witting反应的修正不稳定的叶立德和醛发生的Witting反应生成Z－烯烃，而改进的Schlosser反应可以得到E－烯烃Stetter反应（Michael－Stetter反应）从醛和α，β－不饱和酮可以得到1，4－二羰基衍生物。

Modular Coupling for Parallel Fluid-Structure Interaction Computations

Modular Coupling for ParallelFluid-Structure Interaction Computations Trond Kvamsdal1,Knut Morten Okstad1,Carl Birger Jenssen1and Jørn Amundsen2 Abstract.A parallel CFD code capable of simulatingﬂow within moving boundaries is coupled to a beam el-ement structural dynamics code.The coupled codes areused to simulateﬂuid-structure interaction for a class ofapplications involving long and slender structures,e.g.,suspension bridges and offshore risers.Due to the differ-ence in size and dimensionality of the3D CFD problemon one side,and the essentially1D structure problem onthe other side,the main bulk of the computations are car-ried out in the CFD code.The parallel efﬁciency of thecoupled codes thus rest on the parallel performance ofthe CFD code,and on minimizing the amount of com-munication between the two codes.To reduce the amountof communication between the CFD code and the struc-ture code,the mesh movement algorithm is split into twoparts,where the most computationally intensive part iscarried out in parallel within the CFD code.The resultingcoupled system has a high parallel efﬁciency even if thestructure code runs on a workstation and the CFD coderuns on a parallel supercomputer provided that the size ofthe CFD problem is sufﬁciently large.1INTRODUCTIONThe two(or three)ﬁeld equations describing theﬂuid-structure interaction problem can be solved in a fullycoupled way.In order to account correctly for the inter-ﬁeld coupling effects,such an approach would requirethe formulation of the entire problem in a monolithicsetting,resulting in the embedding of the structural solverwithin theﬂowﬁeld solver or vice-versa.Consequently,it would require a large development work.In addition,the modularity and the speciﬁc character associated witheach disciplinary solver would have to be sacriﬁced to a2COMPUTATIONAL APPROACH2.1Architecture of FSI-systemThe developed FSI-system is based on a staggered solu-tion procedure[1,5].The main principle for a staggered procedure is to solve for the variables of one equation sub-system while keeping the variables of the other sub-system‘frozen’.The frozen variables are then applied as boundary conditions or loads on the active equation sub-system.Such a procedure enables us to use existing codes for the two sub-systems(the CFD and CSD equa-tions)with only minor adjustments to each code.The main programming effort in developing the FSI-system is thus related to the third code entering the system;the coupling module.The FSI-system is designed so that each of the three different codes can run on completely separate computers, and communicate using Parallel Virtual Machine(PVM) message passing.Typically,the CFD-code would run on a large number of processors on a parallel machine,while the CSD-code would run on a workstation or a single node of the parallel machine.The coupler,which con-tains a user interface,is designed to run on the user’s own workstation.A schematic view of the communication be-tween the different codes is shown in Figure1.As we can see,all communication goes through the coupler.The coupler thus has the task of restricting theﬂuid forces acting on the surface of the structure as discretized by the CFD mesh,to the corresponding nodes connecting the beam elements in the structure model.Also,the cou-pler receives the displacements of the structure nodes and computes new mesh coordinates which are passed on to the CFD-code.As described in the next section,to ensure computational efﬁciency and parallel scaleability,only a small part of mesh movement computations are carried out by the coupler,while most of the computations are carried out within the CFD-code.As the structure is assumed to be discretized with1D beam elements,contact interface algorithms have been developed that are capable of(a)transforming surface tractions obtained from the CFD-code to variationally equivalent beam nodal forces and(b)determining the movements of the the contact interface corresponding to the computed beam nodal displacements.2.2Mesh Movement StrategyIn coupled analysis of FSI-problems the displacements of the structure and the use of Arbitrary Lagrangian Euler (ALE)formulations for discretization of theﬂuid domain raises the need for moving the nodes in theﬂuid domain.Figure1.Overview of the FSI systemIn case ofﬂow around slender structures(e.g.,risers and pipelines)with large length to width ratio,large displace-ment of the structure can occur.This implies also large displacements of theﬂuid nodes in the vicinity of the structure.Hence,the choice of algorithm for the mesh movements is important for the accuracy of the numeri-cal simulations.Due to the difference in size and dimensionality of the3D CFD problem on one side,and the essentially 1D structural problem on the other side,the main bulk of computations are carried out in the CFD code.The parallel efﬁciency of the coupled codes thus rest on the parallel performance of the CFD code,provided that the additional mesh movement and communication through the coupler can be carried out in an efﬁcient manner.The problem of moving the mesh to conform with one or more moving bodies as well as a number of non-moving boundaries is global in nature.It is a problem of book-keeping to keep track of several moving bodies and their relative location,but also a mesh generation problem to create a smoothly moving mesh with as little distortion as possible.The global nature of the problem calls for some sort of elliptic procedure as commonly used in mesh generation.Both the elliptic problem and the book-keeping challenge makes it tempting to implement the whole mesh movement procedure as single processor code.It is however clear that a system architecture as shown in Figure1,would not be feasible if at each iteration,all mesh coordinates were to be updated by the coupler and then passed to the CFD code.If the3D CFD problem has size3,such an approach would require the order of3operations on a single processor as well as having to send33values over the network.Since in the CFD code,the computational cost and communication costs are of the order3and2respectively,the couplerCFD in Fluid-Structure Interaction2T.Kvamsdal et al.would then create a scalar bottleneck and an increase of the communication cost of one order of magnitude.On the other hand,embedding the mesh movement algorithm completely within the parallel CFD code would eliminate both the communication overhead and scalar bottleneck, but would instead introduce complicated book-keeping and require the implementation of an elliptic solver withinthe CFD code.Our solution to this problem has been to split the mesh movement in two levels;a global and a local level.The method is linked to the use of structured multi-block mesh generation and thus well-suited for parallel com-putation.A main aspect of multi-block mesh generation techniques is the sub-division of the domain into blocks topologically equivalent to cubes.For problems relevant for FSI-computations the number of blocks are usually a few hundred or less,whereas the number of elements and grid points may be as large as millions.In the global level of the mesh-movement problem an elliptic problem for the location of the block vertices is solved,whereas independent problems for the location of the mesh nodes inside each block are solved afterwards on the local level. Thus,the coupler only has to solve a very coarse elliptic problem,and the communication cost is proportional to the number of blocks,and not mesh points.Paralleliza-tion of the local problem within each block is trivial,as the CFD code is already parallelized over the blocks.The principle of our approach is shown in Figure2. An elliptic problem where the computational blocks are considered as solid elastic blocks areﬁrst solved by the coupler and the updated coordinates of the block corners are passed to the CFD code.Following[6],the blocks of the multi-block mesh can be considered as linear elas-tic bodies,characterized by a Young modulus,,and a Poisson ratio,and each block is regarded as bi-(or tri-)linear isoparametric element,.The mesh move-ment problem then becomes an elliptic problem with only Dirichlet boundary conditions,and it can be solved using any linear solver.This method has the additional advan-tage that the Young’s modulus can vary form block to block,making it possible to keep blocks in the vicinity of the structure almost unchanged in shape,while most of the distortion is taken up by more distant blocks.Once the global mesh movement problem is solved for the corners of the blocks,the updated valuesare sent to the CFD code,where Trans Finite Interpolation(TFI)is used to update the interior coordinates of the blocks.Note that we are using TFI on the displacement,or change between each iteration,of the mesh coordinates.Thus,the overall mesh quality remains as in the initial grid,and if the corner nodes of the block remain unchanged,the mesh within theHost Proc.Elliptic FEMProc. 4Proc. 3Proc. 2Proc. 1TFITFITFITFIFigure2.Mesh movement strategy.block also stays unchanged.This ensures that the mesh retain the properties such as clustering and orthogonality as imposed by the original mesh generation and do not inherit properties of the TFI mesh generation.The present mesh-movement algorithm may also be combined with mesh adaption by means of relocation of nodes.3BENCHMARK RESULTSThe FSI-software used in the present study is composed on the basis of two existingﬁnite element codes,in addi-tion to the developed generic coupling module.The CFD-code used is CBJ(Concurrent Block Jacobi)[3]whereas the structure code is USFOS[2].The capabilities of the CFD-code include time accurate computations on mov-ing meshes based on an ALE-description.Implicit time stepping is used to avoid limitations on the size of the time step for stability reasons.The code is parallelized by means of a domain decomposition,or multi-block tech-nique which also allows for the computation ofﬂowﬁelds in complex geometries.A developed coarse grid correc-tion(CGC)scheme is used to solve in parallel the linear system of equations resulting from the implicit time step-ping.A Smagorinsky sub grid scale model is implemented to facilitate Large Eddy Simulations(LES).Theﬂuid domain of the benchmarktest caseconsists ofCFD in Fluid-Structure Interaction3T.Kvamsdal et al.putational blocks of the benchmark example. 43000grid points in CBJ divided into28computational blocks.The geometry of these blocks is illustrated in Figure3.There are two blocks in the length direction of the bridge.The structure is modeled in USFOS using a single beam element which is attached to a set of springs in each end to simulate the global stiffness of a bridge.The FSI test runs are performed across the NTNU-SINTEF internet with a physical distance of approxi-mately5km between the CFD and coupler hosts.The coupler host is attached to a Ethernet and the CFD host to a FDDI.Between the two systems,PVM messages are transported in four network hops.The CSD application run runs on the same host as the coupler,a2-CPU SGI IRIX system with150MHz R4400processors,whereas the CFD host is a CRAY T3E.In the time step loop,the coupler sends26380bytes to the CFD application and receives33548bytes in return, in average approximately30000bytes.The round-trip time,as measured with3030000byte traceroute(8) packets is75.8ms on the average.The timings listed in Table1give the CPU time used by the CFD code and the rest of the FSI system based on the two-level mesh-movement solver described above. The Table also report the overhead represented by the FSI system and the speed-up for the complete system as a function of the number of processors used by the CFD code.The CPU time for the additional FSI parts,fsi, includes all CPU time associated with FSI.As we can see,acceptable performance is obtained for up to12processors.The CPU time for the FSI parts remain almost constant as expected,while the CFD code shows very good scaleability.This benchmark is overly pessimistic in terms of the scaleability of the complete system,as the FSI part appears as a sequential bottleneckTable1.CFD application scaleability with the two-levelmesh movement solver.cpu[sec.][sec.][sec.][%]294.912.3307.2 4.0 1.0 465.111.176.214.57 4.01238.412.050.423.81 6.1Table2.CFD application scaleability with a one-level meshmovement solver.cpu[sec.][sec.][sec.][%]216.6280.2496.856.4 1.0 454.6280.2334.883.7 1.4812the coupler,and one local part computed in parallel bythe CFD code.The scaleability of the CFD code is veriﬁed to be re-tained for problems larger than3000grid points on eachCPU,which typically is the case for FSI-simulations ofrelevant wind-and offshore engineering problems.In fact,the new results indicate some superscaleability for the4-and8-processor simulations.The reason for this,however,is believed to be caused by less efﬁcient message pass-ing by the2-processor simulation in that each message islarger,and larger messages are fragmented internally onthe CRAY T3E.In addition,the cache/memory ratio isless beneﬁcial when only two processors are used.ACKNOWLEDGMENTThis work was supported by the EC-ESPRIT IV programunder project no.2011.http://tina.sti.jrc.it/FSIREFERENCES[1] C.A.Felippa and K.C.Park,‘Staggered Transient AnalysisProcedures for Coupled Mechanical Systems:Formulation’,Computer Methods in Applied Mechanics and Engineering,24,61–111,(1980).[2]Ø.Hellan,J.Amdahl, B.Brodtkorb,T.Holm˚a s,andE.Eberg,USFOS A Computer Program for ProgressiveCollapse Analysis of Steel Offshore Structures,Users Man-ual,SINTEF Structural Engineering,Trondheim,Norway,April1988.[3] C.B.Jenssen,The Development and Implementation of anImplicit Multi Block Navier–Stokes Solver,Dr.Ing.disser-tation,Department of Mechanical Engineering,The Nor-wegian Institute of Technology,Trondheim,Norway,1992.[4] C.B.Jenssen,J.Bugonovic Jakobsen,I.Enevoldsen,andS.O.Hansen,‘Predicting wind induced motion of suspen-sion bridges using parallel cfd’,in Proceedings of FourthECCOMAS Computational Fluid Dynamics Conference,Athens,Greece,(September1998).[5]P.Pegon and K.Mehr,‘Report and algorithm for the cou-pling module’,Technical Report I.97.77,JRC,Ispra,Italy,(1997).[6]P.Pegon and K.Mehr,‘Rezoning and remeshing of theﬂuiddomain’,TechnicalReport I.98.26,JRC,Ispra,Italy,(1998).[7]K.Randa,A.Atkins,and J.Amundsen,‘Coupling module’,FSI-SD Report R3.3,(1997).CFD in Fluid-Structure Interaction5T.Kvamsdal et al.。

金属催化羰基化合物还原偶联反应的研究进展

金属催化羰基化合物还原偶联反应的研究进展王献友;覃兆海【摘要】Carbonyl reductive coupling reaction was one of the most effective methods to form carbon - carbon bonds, which played an important role in organic synthesis. The reductive coupling of carbonyl compounds were usually made of carbonyl compounds with metal reagents or metal complex function and realize, generally followed the single electron transfer process. Some new application developments of carbonyl compound suchas metal, Titanium, Samarium, Chromium, etc in reductive coupling reaction were summerized.%羰基化合物还原偶联反应是形成碳一碳键最有效的方法之一，在有机合成中占有重要地位。

羰基化合物还原偶联通常由羰基化合物与相应的金属试剂或金属络合物作用而实现，一般遵循单电子转移历程。

本文综述了近年来金属钛、钐、铬等在羰基化合物还原偶联反应中应用的新进展。

【期刊名称】《广州化工》【年(卷),期】2012(040)009【总页数】4页(P3-5,18)【关键词】金属;催化;羰基化合物;还原偶联【作者】王献友;覃兆海【作者单位】河北大学质量技术监督学院,河北保定071002;中国农业大学理学院,北京100194【正文语种】中文【中图分类】O621.3羰基化合物的还原偶联反应一直是有机合成研究领域中的一个热点,广泛地应用于天然产物、农药、医药等精细化工产品的合成.它是形成碳-碳键最有效的方法之一,目前最有效的方法是羰基化合物与金属试剂或金属络合物在有机溶剂中进行还原偶联,羰基化合物还原偶联一般遵循单电子转移历程.近几年来,随着新技术的应用以及新试剂新体系的不断引入,对羰基化合物还原偶联的研究又出现了新的成果.下面就此类反应新研究进展做一详细综述: Mukaiyama等[1]在1973年首次报道了利用低价钛试剂把醛酮还原偶联为烯烃.近年来有关钛试剂的偶联反应又有许多文献报道.2004年,Li等[2]报道了TiCl4(THF)2与两个手性中心的席夫碱L一起来催化芳香醛,所得的频哪醇具有较高的产率和对映选择性.2007年,刘云奎等[3]报道了以一酮二酯为底物,让其在Sm/ TiCl4在THF体系中进行反应,发现反应在回流条件下能顺利地进行,并得到预期的β-环戊酮甲酸酯.由于钛具有很强的脱氧能力,所以没有得到含羟基的产物.Cp2TiCl2在水/THF介质中可以使醛立体选择性地偶联为频哪醇,dl/meso异构体之比可高达99∶1[4].2001年,Yamamoto等[5]报到了由三价钛化合物Cp2TiPh 和Zn引发的分子内和分子间醛的非对映选择性的还原偶联反应,当不加入Ti3+的催化剂时,频哪醇的产率仅仅为13%,而且没有对应选择性.加入催化剂Cp2TiPh时,频哪醇的产率为大于84%,dl/meso异构体的比例也相应提高.Cp2TiPh和Zn催化脂肪醛及芳醛分子内偶联时,频哪醇的产率大于40%,dl/meso异构体之比接近于100∶1.2009年,Paradas等[6]研究了芳香酮在Cp2TiCl2/Mn催化下发生羰基还原偶联反应生成频哪醇,产物同样具有立体专一性.同年王琼[7]采用对二甲苯为溶剂进行金属钛催化芳酮与邻苯二甲酸酐还原偶联反应,反应产物仅为芳酮的自身偶联产物及其中间体的重排频哪酮,而并非芳酮与邻苯二甲酸酐的交叉偶联产物或邻苯二甲酸酐酐自身偶联产物.2010年Okamoto等[8]报道了芳香醛在Ti(O-i-Pr)4/Me3SiCl/ Mg试剂催化下发生分子间偶联反应,生成联苯烯和频哪醇.未加入Ti(O-i-Pr)4或Me3SiCl时,反应不能进行.加入Ti(O-i-Pr)4/Me3SiCl/Mg和路易斯碱(DMA,NMP,Et3N,pyridine)时,反应能够如期进行,得到主产物为联苯烯,特别是Ti(O-i-Pr)4∶Me3SiCl∶Et3N=1.3∶1.3∶2.6(equiv.),40℃反应24 h,联苯烯的产率达到97%,而且具有高度的立体专一性(E/Z=99/1).自从1980年Kagan[9]把二碘化钐(SmI2)引入到有机合成以来,SmI2作为一种醚溶性的优良单电子转移试剂在有机合成中得到了广泛的应用.同时,SmI2的研究也进一步推动了化学家对其它钐试剂如金属钐、SmI3以及有机钐试剂应用于有机合成的研究,发现了一些新反应、新方法[10].2003年,Fan等[11]报道了在SmI2的引发下,酰胺和酮羰基发生分子内还原偶联生成2,3-二取代的吲哚衍生物,作者并做了不同温度下的条件试验,随着温度的改变,两种产物比例也随之改变,65℃时得到以前者产物13为主,在0℃以下主要得到后者产物为14.2005年,Bradley等[12]报道了1,4-二酮在二碘化钐引发下发生分子内还原偶联生成环丁基二醇类化合物,当加入少量的HMPA会有利于关环反应的进行.2006年,Huang等[13]报道了2-酰基苯甲酸乙酯在SmI2的引发下不对称合成手性的苯并呋喃酮类化合物,反应具有高度的对映选择性,ee值大于99%.2008年本课题组成员李洪森等[14]成功的全合成具有很好生物活性的天然产物(+)-rocalamide.其中最为关键的一步就是在SmI2催化酮-酯羰基发生分子内还原偶联,关环生成稠三环.2002年Nair等[15]报道了芳香醛和α,β-不饱和酮在In/ InCl3催化作用下反应生成高立体选择性的频哪醇.2007年, Wang等[16]报道了InCl3/Al体系下的芳香族醛酮类化合物分子间频哪醇反应,作者并对二苯甲酮在InCl3/Al体系下反应进行了条件优化实验.最终提供了一条氯化铟参与的操作方便,而且不需要无水无氧条件合成邻二醇化合物的路线.2003年,Takai等[17]报道了DMF作溶剂,CrCl2-Me3SiCl催化α,β-不饱和酮与脂肪醛发生分子间还原偶联生成频哪醇.在25℃,搅拌反应1 h,产率达到98%(anti/syn=40∶60),而当反应温度升高,anti/syn比例则逐渐降低.2005年Groth等[18]也报道了8种α,β-不饱和醛与脂肪醛在CrCl2-Me3SiCl催化下发生分子间还原偶联生成频哪醇.当R1=R2=tert-Bu时,产物具有很好的立体选择性,anti/syn的比例大于97.5∶2.5,de值大于95%(syn).2009年,Halterman等[19]研究了0.25 M苯甲醛、10mol% CrCl2和过量锌粉在水中进行还原偶联反应,频哪醇的产率为37%(dl/meso=0.7∶1),而苯甲醛直接还原苯甲醇的产率却达到63%.超声波辐射下,铝粉在氟化钾或氟化钠的水溶液中,可使芳香醛快速还原或偶联,生成相应的双分子还原偶联产物和少量单分子还原产物,其中还原偶联产物邻二醇的收率达15%～ 82%.与传统金属催化羰基还原偶联方法相比,超声波辐射反应产物的对映选择性较差[20].2006年,Yuan等[21]报道了铝粉在草酸水溶液中催化芳香醛或芳基甲酮得到产率较高的频哪二醇,缺点是产物立体选择性较差.作者发现脂肪族醛和二芳基酮在同一条件下却不能进行反应.Hirao等[22]报道了Ae2O(AcCl)酰化试剂可以催化苯甲醛还原偶联为频哪醇的反应.以3mol%的VOCl3,2 mol的Ac2O和Zn粉作为共同还原剂,得到了高产率非对映体选择性的邻二酰化醇.作者还报道了TiCl4-AcCl-Al也可起相同催化作用,并对文中不同的催化剂、芳香醛进行了反应产率及立体选择性进行了比较.刘树明等[23]在2002年报道了甲醇做溶剂,芳香醛与锌粉和氢氧化钠溶液室温下搅拌0.5～7 h,收率为17%～96%,通过实验作者发现脂肪醛与酮在相同的反应条件下均没有反应;溶剂和碱的浓度对偶联反应产率也有一定的影响.之后,边延江等[24]研究了Zn-H2O-HOAc体系中芳香醛的还原偶联反应,并分别探讨了锌粉用量,时间,醋酸的体积对邻二醇产率的影响.2008年,Lin等[25]研究了邻卤代芳香醛在催化剂(Ph3P)2NiCl2和还原剂Zn粉共同作用下,生成联苯二醛和二卤化锌;紧接着ZnX2继续催化联苯醛发生分子内频哪醇偶联反应生成9,10-二氢化菲-9,10-二醇.相比于钛和钐,金属锆在有机还原偶联的反应则报道要少得多,Askham等[26]曾报道了Cp2Zr(Me)Cl催化分子间的芳香醛(酮)生成频哪醇,产物具有很好的立体选择性.Mg或LiAlH4在四氢呋喃中还原四氯化锆后得到活性低价Zr,二苯基甲酮被活性低价锆还原偶联为四苯基乙烯.改变ZrCl与二苯基甲酮(M)的摩尔比,结果表明,ZrCl4与M的摩尔比为3时,收率最高[27].超声波辐射下,Mn-NH4Cl-THF∶H2O(1∶4,V∶V)或Mn-MnCl2-THF∶H2O(1∶4,V∶V),于室温2～3 h内可使芳香醛还原偶联成邻二醇,收率为30%～95%.利用超声波辐射下反应时间大大缩短,产品收率提高[28].之后,边延江等[29]报道了La-H2O-THF体系中,超声波辐射下于室温还原芳香醛1 h内可得到收率为52%～89%的邻二醇.而在同样体系中,即使没有超声波辐射而仅搅拌24 h,邻二醇产率也可达到35%～ 67%.2005年,Xu等[30]研究了H2O做溶剂,VCl3和Al作为共同还原剂,11种芳香醛发生还原偶联生成频哪醇,产率为59%～ 84%.在相同的反应条件下,苯乙酮却没有反应生成1,2-二醇.2009年,Sun等[31]报道了手性配体H2L和VO(acac)2-Zn -Me3SiCl共同催化芳香醛偶联生成频哪二醇,当R=p-CH3-OC6H4时,获得手性1,2-二醇的产物具有高非对映选择性(dl/ meso=90/10)和对映选择性(ee=81%,S,S).同年,Maekawa等[32]研究了Mg/TMSCl催化芳香酮(亚胺)和脂肪族醛(酮)之间的频哪醇反应,产物具有较好的产率.羰基化合物还原偶联反应是形成碳-碳键最有效的方法之一,在药物及光活性有机物的合成中占有重要地位.众多实验事实表明,金属钛、钐、铬等是一种应用非常广泛的金属试剂,作为单电子转移试剂可以促进各种还原偶联反应,而且大多数反应都具有反应条件温和、反应速度快、选择性好(立体选择性、对映和非对映选择性)的优点.羰基化合物还原偶联所形成的频哪醇是有机合成中重要的合成反应.羰基化合物还原偶联通常由羰基化合物与相应的金属试剂或金属络合物作用而实现,一般遵循单电子转移历程.反应中除了双分子还原产物外,同时还有单分子还原产物;偶合产物又有两个手性中心,这为片呐醇的有效合成增加了困难.因此,为了有效控制反应的化学选择性和立体选择性,寻求新的金属试剂、新的反应体系和新的方法一直是人们关注和研究的重点.目前的研究热点是构建合适的反应体系,即提高反应的立体选择性. 近年来,随着偶联催化剂的研究越来越深入,作为有机合成工作者来说,在羰基化合物还原偶联反应上会获得更大突破和进展.【相关文献】[1] MUKAIYAMA T.,SATO,T.,HANNA J.Reductive coupling of carbonyl compounds to pinacols and olefins by using TiCl4and Zn[J]. 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coupling (to be constructed by the contractor)

coupling (to be constructed by the contractor)全文共四篇示例，供读者参考第一篇示例：Coupling (由承包商制造) 是一个在工程领域中常见的连接器件，用于连接两个不同的机械部件或管道，使其能够一起运行或传递能量。

在建筑、机械制造、供水系统、供气系统等领域中，coupling 被广泛使用，以确保各种设备和管道的顺畅运行。

承包商在施工过程中通常会根据实际需要制造各种类型的coupling，并按照项目要求进行安装。

在一些特定的工程项目中，承包商可能会根据工程设计图纸中的要求，选择合适的材料和工艺来制造coupling，以满足工程质量和性能要求。

coupling 的制造通常包括以下几个步骤：首先是根据设计图纸确定coupling 的尺寸、材料和工艺要求；然后是选择合适的材料，比如钢、铜、铝等，根据要求进行加工和成型；接着是进行表面处理，比如镀锌、喷漆等，以提高耐腐蚀性能；最后是根据设计要求进行组装和检验。

在制造coupling 的过程中，承包商需要严格控制每个环节，确保coupling 的质量和性能符合标准要求。

这包括材料的选择、加工精度、表面处理质量、组装技术等方面。

只有确保每个环节都符合要求，才能保证coupling 的可靠性和稳定性。

除了制造coupling，承包商还需要根据具体情况选择合适的连接方式，比如螺纹连接、焊接连接、搭接连接等。

不同的连接方式适用于不同的工程环境和要求，在选择时需要考虑材料的性能、连接强度、安装方便性等因素。

在实际施工过程中，承包商可能会遇到各种挑战和问题，比如材料供应不足、加工设备故障、施工现场条件限制等。

在这种情况下，承包商需要灵活应对，及时调整计划，确保coupling 的制造和安装工作顺利进行。

coupling (由承包商制造) 在工程领域中起着重要的连接作用，承包商在制造和安装coupling 过程中承担着重要的责任。

烯烃人名反应

Birch反应用溶解在液氨(liquid ammonia)的碱金属(Li, Na, K)在醇的存在下将芳香环的1,4-还原得到相应的非共轭环己二烯和杂环化合物的过程就称为Birch reduction。

机理Example参考文献：Donohoe，H.J.; Guillermin，J.B.; Calabrese，A.A.; Walter，D.S.Tetrahedron Lett. 2001，42，5841-5844.McMurry Coupling醛或酮在还原性金属和低价态钛的作用下两个羰基缩合去氧得到烯烃的反应。

Example：交叉-McMurry偶联参考文献：McMurry，J. E.; Fleming,M. P. J.Am.Chem. Soc.1974, 96, 4708-4712. Wittig反应用磷叶立德使得羰基进行烯基化的反应，通常得到Z-烯烃为主的产物。

机理Example参考文献:Schweizer，E. E.; Smucher，L.D. .Chem.1966,31,3146-3149 °CDiels-Alder环加成反应EDG = 供电子基团；EWG = 吸电子基团机理Example参考文献：Diels，O.; Alder，K. Ann. 1928,460,98-122.Cope消除反应N-氧化物热消除为烯烃和N-羟基胺Example参考文献：O'Neil，I.A.; Ramos，V.E.; Ellis，G.L.;Cleator，E.; Chorlton，A.P.; Tapolczay，D.J.;Kalindjian，S.B. Tetrahedron Lett.2004,45,3659-3661.Corey-Winter烯烃合成反应二醇用1,1`-硫羰基二咪唑（TCDI）和亚磷酸三甲酯先后处理后给出相应的烯烃。

Example参考文献：Corey，E.J.; Carey，F.A.; Winter，R.A.E.J.Am.Chem.Soc.1965，87，934-935.Glaser Coupling Reaction端基炔烃在氧气中由酮催化发生氧化偶联反应。

四苯乙烯制备及其应用研究综述

收稿日期：2022-02-17作者简介：罗一权（2002-），西南科技大学在读学生，。

四苯乙烯制备及其应用研究综述罗一权，冯亮，郑仁林（西南科技大学生命科学与工程学院，四川绵阳621000）摘要：四苯乙烯具有非常独特的光电特性和生物活性，是一种具有显著聚集诱导发光的分子。

从四苯乙烯的制备出发，简单介绍了四苯乙烯的三种常用制备方法、原理以及近年来四苯乙烯在离子探针、生物检测、有机发光材料等多个领域发挥的巨大作用，其中重点介绍了四苯乙烯及其衍生物作为离子和生物探针方面的研究进展。

最后展望了四苯乙烯及其衍生物的应用前景和短板并提出了目前仍需解决的问题。

关键词：四苯乙烯；聚集诱导发光；制备；应用doi ：10.3969/j.issn.1008-553X.2022.04.003中图分类号：O62文献标识码：A文章编号：1008-553X （2022）04-0010-07安徽化工ANHUI CHEMICAL INDUSTRYVol.48，No.4Aug.2022第48卷，第4期2022年8月1，1，2，2-四苯基乙烯（tetraphenylethylene ，TPE ），其外围苯环呈螺旋桨形结构，是一种典型的聚集诱导发光（Aggregation Induced Emission ，AIE ）荧光发光团[1]。

TPE 的分子结构是非平面的，具有高度动态基团。

由于TPE 分子中四个苯环通过碳碳单键与中间的乙烯基团相连接，因而苯环可以以单键为转轴自由地旋转、振动。

TPE 发光体在溶液中是不发射的，导致无辐射的弛豫过程。

TPE 分子的螺旋构象限制了苯环在聚集时的分子内旋转。

这种对分子内旋转的构型限制[2]阻止了非辐射松弛的途径，因此TPE 发出了荧光。

在聚集诱导发光体（Aggregation-Induced EmissionLuminogen ，AIEgen ）体系中，四苯乙烯及其衍生物因其易于合成、光性能优良、官能团容易修饰等优点而成为研究最广泛、发展最快的一类。

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Okamoto, S.; He, J.; et. al., Tetrahedron Lett. 2010, 51, 387-390.
Intramolecular reactions
非天然产物合成
J. E. McMurry, K. L. Kees, J. Org. Chem. 1977, 42, 2655–2656.
• 双键位阻大，较难形成； • 避免手性碳的消旋化；
• 避免脱卤反应；
钛试剂的选择：
TiCl4 or TlCl3 还原剂的选择：
还原剂 Zn LiAlH4 原料ee值/% 产率/ % 89 89 75 38 E/Z 50/50 40/60 产物ee值/% 93 98
路易斯酸性过强会导致α位的手性碳消旋化
• LiAlH4做还原剂时，有明显的脱溴反应（可能和TiH2
产生有关），且有较多的单 Ben, L.; et. al., Org. Lett. 2014, 16, 4220.
McMurry coupling of aryl aldehydes and imino pinacol coupling mediated by Ti(O-i-Pr)4/Me3SiCl/Mg reagent
Thanks For Your Attention
McMurry coupling
Content
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Introduction Intermolecular reactions
Intramolecular reactions
Summary
McMurry coupling
The McMurry reaction is an organic reaction in which two ketone or aldehyde groups are coupled to an alkene using titanium chloride compound such as titanium(III) chloride and a reducing agent.
低价钛试剂一般由TiCl3经LiAlH4或碱金属或Mg或Zn(Cu)还原形成；
醛、酮的偶联反应可以分子间或分子内方式形成，分别用于链状或环烯烃的合成；
从小环烯烃到大环烯烃，包括索烃和72元大环四醚脂类烯烃均可形成；酮-酮，酮-酯，酮-酰胺羰基间的交叉偶联也可进行。
The End
Mechanism
Features
The low-valent titanium: TiCl3 with (Zn-Cu); At low temperature: the pinacol intermediate may be isolated; At high temperature the alkenes are formed directly; Sterically hindered and/or strained olefins (tetrasubstituted alkenes); Macrocyclization (highdilution); Intramolecular reactions are the fastest for the formation of five- and sixmembered rings and the formation of eight- or higher-membered rings is considerably slower; Aldehydes react much faster than ketones: chemoselectivity; Poor stereoselectivity: preference for (E)-alkenes; Homocoupling and mixed coupling.
Application of McMurry Reaction in Synthesis of Natural Products
Ephritikhine, M., Villiers, C. Modern Carbonyl Olefination 2004, 223-285.
Eguchi, T., Ibaragi, K., Kakinuma, K. J. Org. Chem. 1998, 63, 2689-2698.
Well-controlled intermolecular Mcmurry coupling
——synthesis of a molecular motor
molecular motor: Light/ heat driven configuration transformation
合成的难点：
Mikami, K., Takahashi, K., Nakai, T. J. Am. Chem. Soc.1990, 112, 4035-4037.
Liu, Z., Zhang, T., Li, Y. Tetrahedron Lett. 2001, 42, 275-277.
Summary
McMurry反应是指醛、酮在低价钛的作用下发生还原二聚形成烯烃的反应；
H. Hopf, C. Mlynek, J. Org. Chem. 1990, 55, 1361–1363.
烟草四烯C
Y. Li, W. Li, Y. Li, Synth. Commun. 1994, 24, 721–726.
异石竹烯
J. E. McMurry, D. D. Miller, Tetrahedron Lett. 1983, 1885–1888.