Inter- and intramolecular-bridge-mediated electron transfer in aliphatic halides

Photoinduced nucleophilic substitution of iodocubanes with arylthiolate and diphenylphosphanide ions. Experimental and computational approaches

A new synthetic route to modify the cubane nucleus is reported here. Methyl-4-iodocubane-1-carboxylate (1) and 1,4-diiodocubane (2) were employed as reagents to react with arylthiolate and diphenylphosphanide ions under irradiation in liquid ammonia and dimethylsulphoxide. The reactions proceed to afford thioaryl- and diphenylphosphoryl- cubane derivatives in moderate to good yields. It is also found that the monosubstituted product with retention of the second iodine is an intermediate compound. Mechanistic aspects are supported by DFT calculations.

Photoinduced substitution of the cubane nucleus is reported here.

Experimental and DFT study on the indium-mediated synthesis of benzophenones via arylstannanes

A DFT analysis was performed with the aim to explaining the narrow scope of the indium-promoted reaction of aroyl chlorides with arylstannanes.

Species with negative electron affinity and standard DFT methods. Finding the valence anions

Recently, we have shown that traditional bound-electron DFT models are reliable enough to reproduce negative electron affinities (EA) within a few meV, as long as the valence anion state is found, but they seem to fail in predicting the lowest EA when the ground anion state obtained is non-valence, which holds the extra electron in a diffuse orbital around the molecule; here we propose an alternative approach for finding the valence anion state, based on the stabilization exerted by a polar solvent; the methodology yields correct EA values (i.e. beyond the Koopman's theorem approximation) by gradually decreasing the dielectric constant of the medium.

Radical nucleophilic substitution of 2-(4-halophenyl)-2-methyl-1-chloropropane with enolate ions of ketones

The photoinitiated reaction of 2-(4-halophenyl)-2-methyl-1-chloropropane 2a,b (halogen=Br, I, respectively) with the anions of pinacolone (3a) and acetophenone (3b) either in DMSO or in liquid ammonia are reported. In DMSO, the main reaction is the SRN1 nucleophilic substitution at the aromatic (Csp2-halogen) center with substitution or reduction at the aliphatic (Csp3-Cl) one. In liquid ammonia, the main reaction is substitution at the aromatic C-halogen site. This difference in product distribution is ascribed to modifications in the rate constant of Csp3-Cl dissociation of the radical anions proposed as intermediates in going from DMSO (rt) to liquid NH3 (-33 degrees C).