Quantum calculations of the physical properties (electronic and vibrational), based on density functional theory (DFT) method at B3LYP/6-31G** level of theory, were performed, by means of the Gaussian 09 set of programs, to investigate the effect of the addition of the radical CN on pyridazine molecules. The best geometry, the total energy, frontier molecular orbital energies (HOMO and HUMO), e...

Carbonyl-carbonyl (C=O···C'=O') interactions are ubiquitous in both small and large molecular systems. This interaction involves delocalization of a lone pair (n) of a donor oxygen into the antibonding orbital (π*) of an acceptor carbonyl group. Analyses of high-resolution protein structures suggest that these carbonyl-carbonyl interactions prefer to occur in pairs, that is, one donor per accep...

The addition of AlCl3 to four-coordinate boranes of the general formula (C-N-chelate)BCl2 results in halide abstraction and formation of three-coordinate borenium cations of the general formula [(C-N-chelate)BCl]+. The latter react with both arylstannanes and arylsilanes by boro-destannylation and -desilylation, respectively, to form arylated boranes. Catalytic quantities of AlCl3 were sufficie...

Theoretical calculations were carried out to understand the effect of annulation on the electronic and ligand properties of boron substituted N-heterocyclic carbenes (B-NHCs). Annulation results in a decrease in stability as indicated by the calculated values of singlet-triplet separations and stabilization energies as well as HOMO-LUMO gaps. Annulated B-NHCs are found to be weaker σ-donors but...

Purpurin is a major anthraquinone present in the roots of Rubia cordifolia (madder). known to activate Nrf2 (Nuclear transcription factor erythroid 2-related 2) EpRE (electrophile responsive element) mediated gene expression as potential beneficial effect. This study aimed elucidate balance between electrophilicity or pro-oxidant activity purpurin underlying induction. For this, activation with...

The reference electrophilicity and nucleophilicity scales established at the B3LYP/6-31G(d) level are herein extended by least squares regressions to most common DFT computational methods used in theoretical organic chemistry studies, including B3LYP, MPWB1K, M062-X, ωB97x-D, combination with basis sets of type 6-31G 6-311G different degrees polarization diffuse functions. Excellent linear corr...

ABSTRACT The electrophilicity of (E)-2-aryl-1-cyano-1-nitroethenes is not sufficient to induce a zwitterionic course of their [4+2] cycloaddition to cyclopentadiene. The one-step mechanism of these reactions is indicated by the activation parameters, and the substituent and solvent effects on the reaction. GRAPHICAL ABSTRACT