Spectroscopic study on enantiomeric Ni(II) complexes of porphyrin-porphyrin Tröger's base and porphyrin-chlorin spiro-Tröger's base derivatives supported by DFT calculations.

The chiral properties of nickel(II) complexes of porphyrin-porphyrin Tröger's base and porphyrin-chlorin spiro-Tröger's base with phenyl or 3-methoxyphenyl substitutions in their meso-positions were studied. Enantioseparation of racemic mixtures was investigated via high-performance liquid chromatography (HPLC) on an analytical ReproSil Chiral-NR column. The optimal conditions were utilized for a multimilligram scale isolation with a semipreparative column.

Silicas with Covalently Anchored Fluorosolvatochromic Dyes Suitable for Naked-Eye Detection of Colourless Compounds.

In this work, two stilbene derivatives with different substituents on the phenolic core (phenyl and dimethoxyphenyl) were prepared. The fluorosolvatochromic response of their -propylated derivatives was studied in a solution of twelve different solvents using UV-Vis absorption and fluorescence emission spectra. Both stilbazolium dyes showed a significant negative solvatochromic effect, with a hypsochromic shift in the visible absorption band of approximately 232 nm and 265 nm for phenyl and the dimethoxyphenyl derivative, respectively, when the solvent was changed from water to pyridine.

Experimental, Spectroscopic, and Computational Insights into the Reactivity of "Methanal" with 2-Naphthylamines.

The reactions of 2-naphthylamine and methyl 6-amino-2-naphthoate with formalin and paraformaldehyde were studied experimentally, spectrally, and by quantum chemical calculations. It was found that neither the corresponding aminals nor imines were formed under the described conditions but could be prepared and spectrally characterized at least in situ under modified conditions. Several of the previously undescribed intermediates and by-products were isolated or at least spectrally characterized.

Preparation and Characterization of Metalloporphyrin Tröger's and Spiro-Tröger's Base Derivatives.

A series of metalloporphyrin dimers as Tröger's bases or spiro-Tröger's bases was prepared starting from five different -symmetry porphyrin derivatives substituted in -positions by Ph, 3-MeO-Ph, 4-MeO-Ph, 3,4-(MeO)-Ph, or 3,5-(MeO)-Ph. Free-base porphyrins were converted to metalloporphyrins, which were subsequently nitrated with nickel(II), copper(II), or zinc(II) nitrate to give β-nitrometalloporphyrins. These were further reduced to β-aminometalloporphyrins and treated with a methanal equivalent under acidic conditions to selectively obtain Tröger's base , spiro-Tröger's base , or a mixture of both, in yields up to 41% of and 45% of depending on the reaction conditions used.

Methodology of deconvolution of total solute retention on chemically modified stationary phases to structure specific contributions of bound compounds.

The total solute retention by a chemically modified stationary phase (CMSP) has been shown several times to be a potential tool for studying the binding abilities of the bound compound. In this article, we present a methodology for the deconvolution of the total retention into structure-specific contributions. Three complementary silica-based CMSPs were prepared: 1) non-modified silica, 2) silica modified by syn-bis-Tröger's base (a molecular tweezer) and 3) silica modified by anti-bis-Tröger's base (a non-tweezer molecule).