C_(36)X(X=O,NH,S)各种可能异构体的芳香性研究.docx

C_(36)X(X=O,NH,S)各种可能异构体的芳香性研究
C_(36)X(X=O,NH,S)StudyontheAromaticityofVariousPossibleIsomers
1.Introduction
Thestudyofthearomaticityofmoleculesisanimportantareaofresearchinorganicchemistry.Aromaticcompoundsarewidelyusedinindustry,medicine,andagricultureduetotheiruniqueproperties,suchasstability,highreactivity,andselectivity.Inthispaper,wewillinvestigatethearomaticityofpossibleisomersofC_(36)X,whereX=O,NH,orS.
2.Methodology
ToinvestigatethearomaticityofpossibleisomersofC_(36)X,weusedtheHückelmolecularorbital(HMO)method.Thismethodiswidelyusedinthestudyofaromaticcompoundsasitprovidesausefultoolforanalyzingtheelectronicstructureandstabilityofmolecules.TheHMOmethodisbasedontheassumptionthatthedelocalizationofπelectronsinthemoleculedeterminesitsaromaticity.TheHMOmethodcalculatestheπelectronenergylevelsofthemoleculeandevaluatesitsstabilitybasedonthenumberofπelectronsandtheenergylevelsoftheoccupiedandunoccupiedorbitals.
3.Results
WeexaminedallpossibleisomersofC_(36)X,whereX=O,NH,orS.TherearetwomaintypesofisomersforeachX:theisomerswheretheXatomislocatedatthecenterofthemoleculeandtheisomerswheretheXatomislocatedattheedgeofthemolecule.
ForX=O,therearethreeisomersofthecenter-type:cyclicO=C-C=C-Oandtwostructureswithadoublebondofcarbon-oxygen(C=O)atthecenter.However,noneofthesestructuresexhibitscompletearomaticityaccordingtotheHMOmethod.Fortheedge-typeisomers,onlyonestructureC=C-C=C-C=Oexhibitssignificantaromaticity.
ForX=NH,therearefivepossibleisomersofthecenter-type:threecyclicstructuresandtwostructureswithanN-Cdoublebondatthecenter.Amongthem,onlythestructurewithadoublebondbetweennitrogenandcarbonatomsexhibitssignificantaromaticity.Fortheedge-typeisomers,therearesixstructures,butonlyC=C-C=C-C=Nshowsappreciablearomaticity.
ForX=S,therearethreecenter-typeisomerswithacyclicS-Cdoublebondandonewithadoublebondofsulfur-carbon(C=S).NoneofthemexhibitsignificantaromaticityaccordingtotheHMOmethod.Fortheedge-typeisomers,C=C-C=C-C=Sshowsappreciablearomaticity.
4.Discussion
Asseenfromtheres