Electronic structure and phase stability of oxide semiconductors: performance of dielectric-dependent hybrid functional DFT, benchmarked against GW band structure calculations and experiments

We investigate band gaps, equilibrium structures, and phase stabilities of several bulk polymorphs of wide-gap oxide semiconductors ZnO, TiO2,ZrO2, and WO3. We are particularly concerned with assessing the performance of hybrid functionals built with the fraction of Hartree-Fock exact exchange obtained from the computed electronic dielectric constant of the material. We provide comparison with more standard density-functional theory and GW methods. We finally analyze the chemical reduction of TiO2 into Ti2O3, involving a change in oxide stoichiometry. We show that the dielectric-dependent hybrid functional is generally good at reproducing both ground-state (lattice constants, phase stability sequences, and reaction energies) and excited-state (photoemission gaps) properties within a single, fully ab initio framework

A facile chemoenzymatic approach to chiral non-racemic beta-alkyl-gamma-amino acids and 2-alkylsuccinic acids.A concise synthesis of (S)-(+)-Pregabalin

Both enantiomerically pure antipodes of GABA analogues were prepared as hydrochloride salts, by enzymatic kinetic resolution of their precursors ethyl 2-(nitromethyl)alkanoates. These latter compounds can be easily transformed into enantiomerically pure 2-alkylsuccinic acids by a Nef reaction followed by oxidation. Interestingly, this reaction was particularly easy for the neopentyl derivative (S)-(+)-7d, which underwent conversion into its corresponding succinic acid derivative (S)-()-8d in buffered solution. The absolute configurations of the main compounds of interest involved are given, together with their CD spectr

Photoinduced formation of cubyl aryl thioethers and synthesis of monocubyl analogue of dapsone

1,4-Disubstituted cubyl aryl thioethers were generated from the corresponding iodocubanes and aryl thiolates upon UV irradiation in dimethyl sulfoxide at room temperature. This simple procedure was found to be compatible with a variety of substituted aryl thiolates. This finding paved the way to a synthesis of the monocubyl analogue of dapsone, a key molecule in the treatment of leprosy, also known as Hansen’s disease, and of acne.</p

Photo-induced formation of cubyl arylthioethers, synthesis of mono cubyl analogue of dapsone

1,4-Disubstituted cubyl arylthioethers were generated from the corresponding iodocubanes and aryl thiolates upon UV-irradiation in dimethylsulfoxide at room temperature. This simple procedure was found compatible with a variety of substituted aryl thiolates substituted. This finding paved the way to a synthesis of the mono cubyl analogue of dapsone, a key molecule in the treatment of leprosy, also known as Hansen’s disease, and of acne