The correlation of the rotation about the C α −C′ bond and the pyramidalization of the sp 2 -hybridized carbon atom C′ and its three bonding partners to a flattened tetrahedron in the substructure C β −C α H−C′(O)−OMe of substituted methyl acetates revealed that the two processes are not independent of each other but parts of a common molecular motion, as outlined in the preceding back-to-back paper. In the present study, we generalized the substructure to X β −C α H−C′(Y)−Z with X, Y, and Z = O, N, C, and S, extending the analysis to several hundred thousand structures of the type carboxylates, carboxamides, ketones, imines, olefins, peptides, lactates, carbothioates, and phenyl derivatives, retrieved from the Cambridge Structural Database. ψ/θ Scatter plots of the individual structure points and their averaging in ψ/θ av curves result in wavelike patterns with three maxima and minima and inversion symmetry at ψ = 0°and ±180 for a 360°rotation of C β about the C α −C′ bond. The pyramidalization of the sp 2 -hybridized group C α C i C o C o′ , which is part of the aromatic system, even disturbs the planarity of phenyl rings. Density functional theory calculations confirm the results of the CSD search.

A chiral Schiff base platinum(II) complex 1 bearing polyethylene glycol (PEG) chains was synthesized. The complex was found to melt at 44 °C whereas its non‐substituted analogue 2 has a high melting point (>300 °C). Upon cooling after melting, the complex remained liquid at room temperature over 30 minutes and exhibited yellow phosphorescence. Circularly polarized phosphorescence (CPP) properties were examined and it was found that the absolute value of the luminescence dissymmetry factor (glum) increases significantly in the liquid state compared to the dilute solution state. Herein, we report the first example of CPP from solvent‐free supercooled liquids.

The correlation of the rotation about the bond C′−C α and the pyramidalization of the sp 2 hybridized carbon atom C′ and its three bonding partners to a flattened tetrahedron was investigated for the substructure C β −C α H−C′(O)−OMe. A search in the Cambridge Structural Database (CSD) gave 15,295 structures with a substituted methyl acetate group at the end of the molecules. The scatter plot of the rotation angle ψ = OC′−C α −C β versus the pyramidalization angle θ = O(MeO)C′C α and the ψ/θ av curve show an unusual undulating pattern with three maxima and minima for a 360°rotation about the bond C′−C α . There is no net chiral induction from the (M ψ )/(P ψ ) conformations of the bond C′−C α to the (R θ )/(S θ ) configurations of the flattened tetrahedron because the contributions of the three maxima and minima cancel each other. The wavelike ψ/θ av curve demonstrates that the rotation about the bond C′−C α and the pyramidalization of the group C′(O)(OMe)C α are not independent processes. They are coupled with each other in one common molecular motion. The ψ/θ av curve appears as the third harmonic of a sinusoidal fundamental frequency. DFT calculations of the propanoate anion, methyl propanoate, and methyl 2methylpropanoate confirm the results of the CSD search.

A series of chiral Schiff-base boron difluoride complexes was synthesized and their photophysical properties were examined. These complexes showed multi-colour (blue, yellow and red) photoluminescence in solution and in the...

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Circularly polarized luminescence (CPL) has been researched for various applications by control of characteristics such as chirality and magnitude. Supramolecular chirality has been prepared by vortex motion as a mechanical stimulus; however, CPL has yet to be controlled precisely and reproducibly. In this work, the first precise control of CPL under vortex flow conditions at an air‐water interface is reported. The supramolecular chirality of aggregates consisting of an achiral trans‐bis(salicylaldiminato)Pt(II) complex bearing hexadecyl chains is induced and controlled with vortex flow at the air‐water interface, whereas the complex naturally forms an achiral amorphous solid with non‐chiroptical properties under non‐vortex conditions. The CPL direction and magnitude (glum value) of the Pt(II) complex aggregates can be adjusted precisely according to the vortex conditions, including the rotatory direction and flow rate. Vortex‐flow‐induced emission enhancement is also observed upon an increase in the rate of the vortex flow.

Scatter plot analyses for 14,169 phenylethanes of the substructure C β -C α H 2 -Ph with three open coordination positions at C β and 150,568 phenylethanes of C β -C α HX-Ph with an additional open coordination position X at C α have been performed, based on searches in the Cambridge Structural Database. The correlation of rotation angle ψ = C β −C α −C i −C o with a pyramidalization angle θ = C o −C o′ −C i −C α in a 360°r otation about the bond C α −C i reveals a sinusoidal pattern with three maxima and minima, whereas the correlation of rotation angle ψ with bond angle ω = C β −C α −C i and bond length d = C β − C α results in sinusoidal patterns with two maxima and minima. A total of 3993 nitro derivatives of the substructure C β -C α HX-NO 2 confirm the results and show that atoms C i /C o /C o′ in the phenyl compounds can be replaced by atoms N/O/O′ without any change in the two-and threefold patterns. In 15,295 methyl acetates of the substructure C β -C α HX-C′(O)OMe, pyramidalization of the group C α C′(O)OMe results in a chiral flat tetrahedron with four different corners. (R θ )/(S θ ) selectivity in the configuration of the tetrahedron is induced by the bonds C α −C β , C α −H, and C α −X, emanating from the tetrahedral center C α . It is surprising that bonds as different as C α −C β , C α −H, and C α −X (X = H, C, N, O, S, etc.) give almost the same induction intensities.

Invited for this month's cover picture are the groups of Masahiro Ikeshita and Takashi Tsuno at Nihon University and Yoshitane Imai at Kindai University (Japan). The cover picture shows the comparison of circularly polarized luminescence (CPL) properties of square planar platinum(II) complexes with different coordination geometry. Computational studies have been carried out to investigate these structure‐dependencies, and revealed that the distortion of the coordination geometry results into an enhancement the chiroptical responses of these compounds. Read the full text of their Research Article at 10.1002/open.202100277.