Michele Usai

A re-examination of the methylenation reaction

A re-examination of the methylenation reaction of 1-hydroxy-2-mercapto-, 1,2-dihydroxy- and 1,2-dimercapto-substituted benzenes by bromochloromethane with cesium carbonate shows that these substrates give mixtures of five- and ten-membered benzocondensed heterocyclic compounds and in some cases even dibenzodioxines.

DFT and multinuclear magnetic resonance studies of diazenedicarboxylates and related compounds

A number of diazenedicarboxylates have been studied by multinuclear magnetic resonance (17O, 15N, 13C) and compared with analogous fumaric, maleic, and phthalic diesters; the investigation of selected compounds of these classes was complemented by density functional theory (DFT) calculations using a polarizable continuum model (PCM) for the solvent, employing the PBE0 functional together with the 6‐311G(d,p) basis set for geometry optimization, and the 6‐311 + G(2d,p) basis set for calculating the NMR shielding using the gauge‐including atomic orbital (GIAO) method. This combined approach provided important information about the preferred conformations in chloroform and their influence on the NMR parameters. Copyright