Chemistry Publications Chemistry 9-29-2007 Sulfur and Selenium Ylide Bond Enthalpies Stacey A. Stoffregen Iowa State University Ryan D. McCulla Iowa State University Robert Wilson Iowa State University Samuel Cercone Iowa State University Jennifer Miller Iowa State University See next page for additional authors Follow this and additional works at: http://lib.dr.iastate.edu/chem_pubs Part of the Organic Chemistry Commons, Other Chemistry Commons, and the Polymer Chemistry Commons The ompc lete bibliographic information for this item can be found at http://lib.dr.iastate.edu/ chem_pubs/156. For information on how to cite this item, please visit http://lib.dr.iastate.edu/ howtocite.html. This Article is brought to you for free and open access by the Chemistry at Iowa State University Digital Repository. It has been accepted for inclusion in Chemistry Publications by an authorized administrator of Iowa State University Digital Repository. For more information, please contact
[email protected]. Sulfur and Selenium Ylide Bond Enthalpies Abstract The bond dissociation enthalpies (BDEs) of sulfur and selenium ylides have been estimated by applying MP2/6-311++G(3df,2p)//MP2/6-31G(d,p), G3, and other computational methods. Computed sulfoxide bond enthalpies were compared to experimental results to ensure the reliability of the computational methods before extending to related compounds. The examined ylides include the following: sulfoxides, sulfilimines, S,C-sulfonium ylides, and selenoxides. Selenoxides have BDEs about 10 kcal/mol smaller than the corresponding sulfoxides. N-H sulfilimines and CH2-S,C-sulfonium ylides have low BDEs, unless the sulfilimine or S,C-sulfonium ylide is stabilized by an electronegative substituent on N or C, respectively.