Quantum Chemistry Study On The Catalytic Activity Of Uranyl-salophen Complexes

Asymmetric synthesis of organic chemistry subject in recent years is anextremely important and dynamic field of research, to be more widely used in thestructure and stereochemistry complex in natural product synthesis. Previously,acquire the method of chiral product mainly split method, get the product first, andthen split the product. This method is very complicated, difficult and inefficient,meaning that half of the product to be lost, causing the huge waste of materials andLabour. At present, this problem have been solved: the asymmetric synthesis,namely choose a chiral induction of catalyst. Uranium and its compounds have somedifferent from other elements and compounds of special molecular recognition andcatalytic performance, the use of uranium compounds as catalysts has become aresearch hotspot in recent years. This paper uses Gaussian09quantum chemistrycalculation software, several uranyl-Salophen complexes were calculated by B3LYPmethod of density functional theory (DFT), and the geometries, electronic structure,IR spectrum, thermodynamic properties and chemical shifts were discussed andanalyzed. We also studied complexes of uranyl-Salophen complexes formed withcyclohexenone, obtained three uranyl-Salophen complexes of cyclohexenonecatalytic activity. These studies illustrate the structure of three complexes, whileproviding a reference for the experimental research and a further study of therelationship with uranyl-Salophen Structure and properties of the foundation.The first chapter mainly introduces the background and significance of thistopic research. Among them, this paper expounds the schiff base and its complexes、asymmetric synthesis and uranium and its complexes. Then combines with thesubject content of the project, and puts forward the research ideas and contentThe second chapter mainly introduces the theoretical basis of density functional theory. First, the historical background of the density functional theory revealsarising from the development of quantum chemistry. Then this paper expounds thedeveloping process of the density functional theory: Thomas-Fermi�'Hohenberg-Kohn�'Kohn-sham, And introduces two kinds of commonly usedexchange related energy functional: local density approximation and generalizedgradient approximation. Finally, a simple Gaussian calculation software isintroduced.The third chapter By the salicylaldehyde、1-2phenylenediamine、salicylaldehydederivative（3-benzene salicylaldehyde）formed tetradentate schiff base ligandsSalophen and UO2+form uranyl-Salophen complexes as the calculating model, usesGaussian09quantum chemistry calculation software, three Uranyl-Salophencomplexes were optimized using density functional theory (DFT) methods atB3LYP/6-31G,6-31G**,6-311G**levels. The geometries, electronic structure, IRspectrum, thermodynamic properties and chemical shifts were discussed andanalyzed. The results show that:(1) the geometry structure of three uranyl-Salophencomplexes is almost identical at B3LYP/6-31G,6-31G**,6-311G**levels, its structurehas C1symmetry.(2) Three kinds of uranyl-Salophen complexes in the order ofcatalytic activity of as: complex3>complex2> complex1, Shows that the role ofcomplex3with the strongest nucleophiles.(3) U of three uranyl-Salophencomplexes still have the bonding ability, such as having to accept a lone pair ofelectrons of O:, which can be weaken the O=C bond, playing a role in theactivation of enone. Three kinds of complexes of U accept O: order of the ability ofthe lone pair electrons: complex3>complex2> complex1.The fourth chapter with uranyl-Salophen complexes with cyclohexene ketone toform complex as the model, uses Gaussian09quantum chemistry calculationsoftware by density functional theory (DFT) B3LYP/6-311-g**method, for the studyof research. The results show that:(1)Three kinds of uranyl-Salophen complexes andcyclohexene ketone after complexation, the whole molecule electrophilic indexdecrease, electronegativity decrease.(2) Three kinds of uranyl-Salophen andcyclohexene ketone charge distribution changes obviously after coordination, C=C and C=O to weaken the conjugation effect between.(3) Three kinds ofuranyl-Salophen complexes of cyclohexene ketone activation is feasible inthermodynamics. They cyclohexenone activation order of strength: complex3>complex2> complex1.The fifth chapter mainly research contents of this paper made a summary, pointsout the research significance of this topic, and discussed in subsequent work...