Photochemistry of n-acetyl-, n-trifluoroacetyl-, n-tosyl- and n-mesyl dibenzothiophene sulfilimine

ORGN 488

Vasumathi Desikan, vasu@iastate.edu1, Yonglin Liu2, John P. Toscano, jtoscano@jhu.edu2, and William S. Jenks, wsjenks@iastate.edu1. (1) Department of Chemistry, Iowa State University, 3801 Gilman Hall, Ames, IA 50011, (2) Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218
We have recently studied the photochemistry of N-benzoyldibenzothiophene sulfilimine,1, by direct TR-IR spectroscopy and steady-state product distribution analysis. Evidence from spectroscopic and steady state analyses suggest the presence and likely sources for the intermediates, namely, phenyl isocyanate and singlet and triplet benzoylnitrene, formed upon photolysis of 1. Other derivatives of dibenzothiophene-based sulfilimines such as the N-acetyl, N-tosyl-, N-mesyl-, and N-trifluoroacetyl analogues are currently being investigated for the formation of reactive intermediates upon photolysis. The N-acetyl derivative gives rise to predominantly singlet nitrene derived products and the photochemistry appears to be similar to 1. However, the N-tosyl-, N-mesyl-, and N-trifluoroacetyl sulfilimines differ substantially from 1 in yielding products primarily from the triplet manifold upon direct excitation. A detailed investigation of the products, formed upon direct and sensitized photolyses of the title compounds, is currently in progress to unambiguously establish the presence and multiplicity of the reactive intermediates.
 

Physical Organic Chemistry, Metal-Mediated Reactions, Asymmetric Reactions and Syntheses
8:00 PM-10:00 PM, Tuesday, August 21, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Organic Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007