title: Ab initio investigation of the fragmentation of 5,5-diamino-substituted 1,4,2-oxathiazoles.
abstract: The mechanism for the fragmentation of 5,5-diamino-1,4,2-oxathiazole derivatives has been studied at the CCSD(T)/6-311+G(3df,2p)//MP2/6-31+G(2df,p) level of theory. The calculations suggest that the fragmentation occurs via a stepwise process involving the formation of polar intermediates that lie in shallow potential wells. We find a large thermodynamic driving force for fragmentation, which together with a weakening of the C-S bond through electron donation by the amino substituents provides the impetus for a low-barrier fragmentation.
authors.affiliation: School of Chemistry and ARC Centre of Excellence for Free Radical Chemistry and Biotechnology, University of Sydney, Sydney, NSW 2006, Australia.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: O'Reilly
authors.forename: Leo
authors.initials: L
authors.lastname: Radom