title: 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. Incorporation of the S or Se into a thiophene or selenophene-type ring lowers the BDE for the ylide.
authors: Department of Chemistry, Iowa State University, Ames, Iowa 50011-3111, USA.
authors: Stacey A
authors: SA
authors: Stoffregen
authors: Ryan D
authors: RD
authors: McCulla
authors: Robert
authors: R
authors: Wilson
authors: Samuel
authors: S
authors: Cercone
authors: Jennifer
authors: J
authors: Miller
authors: William S
authors: WS
authors: Jenks