Health & Environmental Research Online (HERO)


Print Feedback Export to File
4181608 
Journal Article 
Determination of sulfoxide bond dissociation enthalpies of dibenzothiophene S-oxide derivatives with computational methods 
Zhang, M; Welch, BK; Hasanagic, M; Fritz, A; Mcculla, RD 
2014 
Yes 
Journal of Physical Organic Chemistry
ISSN: 0894-3230 
27 
630-639 
Photodeoxygenation of dibenzothiophene S-oxide (DBTO) has been suggested as a clean way to generate atomic oxygen in solution. Sulfoxide bond dissociation enthalpies (BDEs) are important to the quantum yield and mechanism of this photodeoxygenation. In this study, BDE of substituted DBTO molecules with various functional groups were determined using M062X/aug-cc-pV(T + d)Z and MP2/aug-cc-pV(T + d)Z levels of theory. The sulfoxide BDE was determined using an isodesmic reaction. The observed effect of substitution was that functional groups with negative sigma(para) values (electron donating) strengthen the sulfoxide bond and that substituents with positive sigma(para) values (electron withdrawing) weaken the sulfoxide bond. The Mulliken charge on sulfur for DBTO and the corresponding dibenzothiophene were identified as a suitable indicator of the predicted S-O BDE. Moreover, steric and hydrogen bonding interactions were found to affect sulfoxide BDE for certain functional groups when located at the 1 or 4 positions of the substituted DBTO. Copyright (C) 2014 John Wiley & Sons, Ltd. 
BDE; bond dissociation enthalpies; computational; dibenzothiophene S-oxide; Mulliken charge; photodeoxygenation; substituent effects; sulfoxide