目录第一章绪论.............................................................................................31.1课题意义...........................................................................................31.2立题思想...........................................................................................31.3过渡金属催化剂...............................................................................3第二章理论基础......................................................................................42.1密度泛函理论(DFT).....................................................................42.2过渡态理论....................................................................................52.3量子化学软件................................................................................5第三章钴催化不对称反应生成环丁酮的机理研究...............................63.1反应背景........................................................................................63.2计算方法........................................................................................73.3反应机理.........................................................................................73.3.1醛基脱氢过程……………………………………………....83.3.2碳碳双键加氢过程……………………………………………………….....93.3.3分子内成四元环过程………………………………………………………………………......9参考文献.....................................................................................................10致谢............................................................................................................12钴催化不对称反应生成环丁酮的机理研究摘要：大多数分子内加氢酰化反应优先生成环戊酮而不是环丁酮。其中有两个例外，它们都使用Rh催化带有甲氧基指导基团的底物，通过氧化加成活化醛C-H键以生成酰基金属氢化物中间体。然后烯烃插入该中间体，生成六元和五元金属环。一般来说，六元金属环易发生还原消除，在热力学和动力学上有利于产生环戊酮产物。此外，实现五元金属环的还原消除是具有挑战性的。本次研究中涉及到利用过渡金属（Co）生成四元环，颠覆了加氢酰化反应的通常区域选择性。本文应用密度泛函理论(DFT)(B3LYP/6-31G(d)),去寻找可能存在的过渡态、中间体，通过理论计算研究了钴催化不对称反应生成环丁酮的机理。计算结果表明，首先钴配合物催化剂与底物发生碳碳双键配位作用，然后醛基中的碳氢键断裂，碳碳双键加氢，最终钴配合物催化剂从体系中分离，生成四元环的过程很有可能是该反应的机理。关键词：加氢酰化反应；过渡金属钴催化剂；密度泛函理论AbstractMostintramolecularhydroacylationprovideexclusiveaccesstocyclopentanonesinpreferencetocyclobutanones.However,therearetwoexceptions,bothofwhichusesubstratesbearingamethoxy-directinggroupunderRhcatalysistoactivatealdehydeC−Hbondsthroughoxidativeadditiontoformanacyl-metal-hydrideintermediate.Fromthisintermediate,olefininsertionresultsinanequilibriummixtureofthesix-andfive-memberedmetallacycles.Ingeneral,reductiveeliminationfromsix-memberedmetallacyclesisthermodynamicallyandkineticallyfavoredtogeneratethelessstrainedcyclopentanoneproduct.Moreover,achievingreductiveeliminationfromafive-memberedmetallacycleischallenging.Ratherthanrelyingonapreciousmetal,weproposeusingatransitionmetal(Co)tooverturntheusualregioselectivityofhydroacylationtofavorthefour-memberedring.Inthisarticle,densityfunctionaltheory(DFT)(B3LYP/6-31G(d))wasusedtofindpossibletransitionstatesandintermediates.Themechanismofcobaltcatalysisforenanti...
