Ricerc@Sapienza

The conformational and stereodynamic properties of a pyrene-substituted thioethyl-porphyrazine (PzPy) promising as dye for organic optoelectronic applications and light harvesting systems, have been investigated by Density Functional Theory computations and variable temperature NMR and HPLC. In PzPy rotation around the pyrene-macrocycle bond is hindered and then the molecule displays atropisomerism existing as a couple of enantiomers, thus representing the first chiral alkyl-porphyrazine reported in the literature.

The VCD spectra of several chiral compounds containing the CF3 group are reviewed and analyzed. The list of compounds contains pharmaceutically relevant molecules as well as simple model molecules, having the value of case studies. In particular we point out the importance of the sign of the VCD band relative to some stretching normal mode of CF3 in the region 1110–1150 cm−1, as diagnostic of the configuration of stereogenic carbons C* to which the CF3 group is bound: the correspondence (−) ↔ (R) and (+) ↔ (S) holds for 100% of 1-aryl-2,2,2-trifluoroethanols.

The assignment of the absolute configuration (AC) of two conformational flexible organic molecules by
means of TD-DFT simulation of the electronic circular dichroism (ECD) spectra is presented. The factors
leading to a reliable assignment were evaluated in the various steps of the process. The effects of
different functionals and basis sets in the geometry optimization step is very limited in terms of the
resulting optimized geometries, whereas the inclusion of the solvent in the calculations has a much

In previous studies, Okamoto et al. described the results of the exceptionally large chiral recognitionof 2-(benzylsulfinyl)benzamide onto a coated-type chiral stationary phase based on cellulose tris(3,5-dichlorophenylcarbamate).