Self-Sensitized Photooxygenation of 2 H -Pyrans: Characterization of Unexpected Products Assisted by Computed Structural Elucidation and Residual Dipolar Couplings Martín J. Riveira, Pablo Trigo-Mouriño. Eduardo Troche-Pesqueira, Gary E. Martin , Armando Navarro-V á zquez , Mirta P. Mischne, Roberto R. Gil J. Org. Chem. 2015 , 80 , 15 , 7396-7402 Publication Date : June 10, 2015 https://doi.org/10.1021/acs.joc.5b00817 Abstract : The UVA (350 nm) irradiation of an α-pyran in the presence of oxygen led to the unexpected formation of a tetraoxygenated compound whose structure could not be unambiguously determined on the basis of conventional 1H–13C correlated experiments. 1,1-ADEQUATE (adequate double quantum transfer experiment) and 1,n-ADEQUATE combined with computer-assisted structure elucidation software led to two structural possibilities involving the formation of either an epoxide or an oxetane. Residual dipolar couplings allowed not only the identification of t...
