Oxidation of
a mixture of deuterated -tocopherol (9) and -tocopherol (10). The corresponding NMMO-complexes
produce the symmetric dioxocine dimers 11 and 12 (symmetry indicated by
the dashed lines) and the “mixed” dimer 13 in which the two parts can be distinguished by NMR spectroscopy. The bent
arrows indicate the long range HMBC connectivities that prove the presence of
the dibenzodioxocine structure.
