The present communication-reports a study on the variation of some structural and electronic properties related with electron conduction for the series of compounds represented by the formula Ph-(C2+nN4-nHn)-Ph, n=0-4. Properties such as planarity, aromaticity, band gap, and adiabatic electron affinity were analyzed from a theoretical perspective as a function of the number of nitrogen atoms in the molecular structure.

Different partial charge distribution methodologies (Mulliken, Löwdin, Hirshfeld, Natural Population Analysis, Merz–Kollman Electrostatic Potential) were used for charge determination in manganese and zinc Schiff base complexes that are isostructural analogs. Chemical reliable clusters were chosen on the ground of experimental X-ray data. Packing effect on charges was found to be negligible. All calculation employed non hybrid ab-initio GGA PBE density functional method with conjunction of different basis sets to show small influence of basis set incompleteness. On the ground of chemical bonding theory Hishfeld partial charge definition was found to be most reliable in different situation – different spin states, H–bonding, molecular crystal and clusters.

The reaction of substituted furans a-c and Danishefsky's diene which yield 5-benzofuranol derivatives has been studied using the hardness, the polarizability and the electrophilicity of the corresponding D-A primary adducts as global reactivity indexes. The main objective of this work is to investigate the power of these global indexes in predicting the major regioisomer. It has been demonstrated that both the hardness as well as the electrophilicity power of the adducts are appropriate descriptors for predicting the major product of the reactions at least in the cases study here. The maximum hardness principle and the minimun electropilicity principle are obeyed in these regiospecific Diels–Alder reactions. The stereoselectivity of the D-A reactions has also been studied.

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A comprehensive MP2/6-311+G(d,p) and B3LYP/6-311+G(d,p) study of the aromatic character of phospholes, Pn(CH)4-nPH with n = 0-4 was conducted. For this purpose, the structures for these compounds were optimized at both theoretical levels and different magnetic properties (magnetic susceptibility, χ, magnetic susceptibility anisotropy, χanis, and the nucleus-independent chemical shifts, NICS) were evaluated. For comparison, these magnetic properties were also calculated in the optimized structures with planarity constraints. We have also applied the ACID (anisotropy of the current-induced density) method in this analysis. The main conclusions are the aromatic character of these compounds, the relationship between aromaticity and planarity and the importance of other factors in this aromaticity.

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Complexes formed by anions and substituted molecular bowls were studied by means of computational calculations with density functional theory methods. An empirical dispersion term was included to correct the well known flaws of common functionals to describe dispersion interactions. The modified bowls consisted of corannulene molecules substituted with five or ten F, Cl, or CN units, whereas Cl-, Br- and BF4 - where the anions considered. Substitution with F, Cl and CN produces an inversion of the molecular electrostatic potential of the bowls, which become positive over the two faces of the bowl, therefore interacting favorably with anions. Three different structures were found for each of the complexes, corresponding to one arrangement with the anion interacting with the concave side of the bowl and two different arrangements with the anions interacting with the convex side of the bowl. The strength of the interaction roughly follows the values of molecular electrostatic potential, being more stable as more positive is the potential. However, the role of dispersion arises as essential for having a correct order of stabilities. In fact, when dispersion is included, most complexes are more stable by the concave face, where the closer proximity of the atoms allows for a larger dispersion effect. Also, it is dispersion which makes the complexes formed with a larger anion as BF4 - as stable as those formed with Cl- or Br-. The results suggest the possibility of employing these substituted molecular bowls as receptors for anions with a preferential concave complexation, specially for structured anions where dispersion effects will be larger.

The dependences of differential spectral parameters (Δδi H) in spectra NMR 1H of monosubstituted benzenes C6H5X on substituent constants (σ) were investigated. The best correlation was founded for set of para-Brown's constants (σ+).

An efficient and controlled Pd−catalyzed synthesis of attached-ring bis(dihydropyran) fused cyclobutenes via alkyne dimerization followed by double [2+2] cyclization of the resulting bis(allenyne) in a domino sequence has been accomplished.

Studies on the stereoselective phenylselenoetherification of (Z)- and (E)-hex-4-en-ols is described. (Z)-Alkenol is envisage to facilitate the 5-exo favored cyclization, while (E)-izomer facilitate the 6-endo favored cyclization. Diastereomeric ratio of the cyclic products depends on counterion and reaction temperature. We found that external additives, such as pyridine and some Lewis acids coordinating to the electrophilic species are used to control the course of cyclizations with high degrees of efficiency and improve the level of stereoinduction. The course of cyclization can be directed as desired by the choice of the electrophile and the additives used in the reaction.