The combination of electronic circular dichroism spectroscopy (ECD), X‐ray diffraction, and theoretical calculations permitted a detailed description of an unexpected chirality transfer in triphenylacetamides, which is achieved solely through weak intramolecular interactions. The observed phenomenon proceeds as a cascade process. The triphenylacetamide chromophore is sensitive to even small changes in the relative size of the substituent attached to the stereogenic center. Substitution at the stereogenic center influences helicity of the distal trityl chromophore but does not affect its propeller shape. Deformation of the propeller shape and consequent loss of its C3 symmetry results mainly from substitution of the amide hydrogen and is connected with an increase in steric hindrance. As an outcome of our studies, a model of optical activity of chiral triphenylacetamides is proposed. The performed X‐ray studies revealed that this novel class of chiral compounds is likely to be of additional value due to the porosity of the crystals.

Synthesis and detailed experimental and theoretical study on new urea and thiourea derivatives of chiral trianglamine are presented. In solution, the urea derivative of the trianglamine adopts cone conformation, whereas a respective thiourea derivative exists in solution predominantly as a partial cone conformer. In the crystalline phase, the thiourea trianglamine derivative adapts partial cone conformation. In the solid state, the two symmetry independent molecules of thiourea trianglamine create bilayers, containing molecules arranged in a zipper motif. The bilayers are separated by channels filled with disordered solvent molecules. The thiourea derivative of trianglimine appeared to be a simple, low molecular weight supergelator that formed stable chiral metallogels in N,N-dimethylformamide with Ag(I), Cu(I). and Cu(II) salts. The enantiomeric enrichment of the macrocycle is a necessary condition for effective gelling because neither racemic nor enantiomerically enriched samples (up to 50% ee) form metallogels. The metallogels formed from silver cations and thiourea trianglamine show reversible thixotropic property rarely observed in metallogels.

A combination of experimental methods (ECD, X-ray diffraction) and theoretical calculations allowed the description of chirality transfer in bis(triphenylacetamides). For the first time it has been shown that effective helicity induction in a trityl chromophore is not only due to the presence of stereogenic center(s) but is also caused by other chirality inductors such as an axis of chirality. For all experimental and computed ECD spectra a uniformly identical sequence of signs of the Cotton effects has been found: negative at around 215 nm and positive below 200 nm. This result can only be explained by the dependence of the ECD spectra on the R absolute configuration of the proximal stereogenic element. The chirality transfer is achieved through a series of weak intramolecular interactions. Helicities of the trityl chromophores and their propeller shapes are influenced by the structure of the chiral inductor and the steric hindrance at amide nitrogen atoms. The stereogenic centers in the diamide unit act independently as chirality inductors and the direct trityl/trityl interactions are only rarely observed.Characteristic for the investigated crystals is the complete hindrance of the amide NH groups and their inability to be involved in any intermolecular interactions as well as their highly restricted ability for the formation of intramolecular hydrogen bonds. This results from the presence of Tr groups, which act as supramolecular NH protecting groups, especially when attached to the rigid carbocycles.

The chiral, triangular-shape hexaimine macrocycles (trianglimines), bearing bulky alkynyl or aryl substituents were synthesized and studied by means of experimental and theoretical methods. The macrocyclization reactions are driven by the extraordinary stability of the trianglimine ring and provided products with high yields. Electrostatic repulsion between imine nitrogen atoms and the substituents forced an anti conformation of the aromatic linkers. Although the DFT-optimized structure of 7 is D symmetrical, in the crystal, the macrocycle adopts a bowl-like molecular shape. The macrocycle self-assembles into tail-to-tail dimers by mutual interdigitation of aromatic moieties. In contrast, macrocycle 8 adopts a rigid pillararene-like conformation. The nature of the substituent significantly affects the electronic properties of the linker. As a result, unexpectedly high exciton Cotton effects are observed in the electronic circular dichroism (ECD) spectra. The origin of these effects was subject of an in-depth study.

A mixture of two diastereomers with the configurations (3aS,7aS,1'R) and (3aR,7aR,1'R) forms co-crystals in which there is one unique molecule in the asymmetric unit, but the molecule displays disorder which is a result of the presence of the two diastereomers at the same crystallographic site. Theoretical calculations carried out by the DFT method with the 6-311++G(2df,p) basis set allowed for the estimation of the energy difference between the two diastereomers both in the isolated and the solid state, while the natural bond orbital (NBO), Mulliken, natural population (NPA) and CHelpG analyses helped to establish the electronic structure of the thazolidin-2-imine fragment.

We have proven the usability and versatility of chiral triphenylacetic acid esters, compounds of high structural diversity, as chirality-sensing stereodynamic probes and as molecular tectons in crystal engineering. The low energy barrier to stereoisomer interconversion has been exploited to sense the chirality of an alkyl substituent in the esters. The structural information are cascaded from the permanently chiral alcohol (inducer) to the stereodynamic chromophoric probe through cooperative interactions. The ECD spectra of triphenylacetic acid esters are highly sensitive to very small structural differences in the inducer core. The tendencies to maximize the C–H···O hydrogen bonds, van der Waals interactions, and London dispersion forces determine the way of packing molecules in the crystal lattice. The phenyl embraces of trityl groups allowed, to some extent, the control of molecular organization in the crystal. However, the spectrum of possible molecular arrangements is very broad and depends on the type of substituent, the optical purity of the sample, and the presence of a second trityl group in the proximity. Racemates crystallize as the solid solution of enantiomers, where the trityl group acts as a protecting group for the stereogenic center. Therefore, the absolute configuration of the inducer is irrelevant to the packing mode of molecules in the crystal.

Stereodynamic trityl group, utilized as a reporter of chirality, hampers hydrogen bonding network in optically active urea and thiourea derivatives.

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