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Supramolecular structures of organic molecules on planar nanocarbon surfaces, such as highly oriented pyrolytic graphite (HOPG), have been extensively studied and the factors that control them are generally well‐established. In contrast, the properties of supramolecular structures on curved nanocarbon surfaces like carbon nanotubes remain challenging to predict and/or to understand. This paper reports an investigation into the first study of the supramolecular structures of 5,15‐bisdodecylporphyrin (C12P) on chiral, concentrated single‐walled carbon nanotubes (SWNTs; with right‐handed helix P‐ and left‐handed helix M‐) surfaces using STM. Furthermore, the study is the first of its kind to experimentally assign the absolute‐handedness chirality of SWNTs, as well as to understand their effect on the supramolecular structures of organic molecules on their surfaces. Interestingly, these SWNT enantiomers resulted in supramolecular structures of opposite chirality based on the handedness chirality. With molecular modelling, we predicted the absolute‐handedness chirality of SWNTs, before demonstrating this experimentally. By using the STM imaging technique, the single‐walled carbon nanotube (SWNT) absolute‐handedness of chirality has been experimentally investigated using supramolecular structures of porphyrin derivatives (C12P). Two opposite chiral supramolecular structures have been observed based on the SWNT enantiomers handedness of chirality (see figure). [ABSTRACT FROM AUTHOR]

Choosing the optimal catalyst for a new transformation is challenging because the ideal molecular requirements of the catalyst for one reaction do not always simply translate to another. Large groups at the 3,3′ positions of the binaphthol rings are important for efficient stereoinduction but if they are too large this can lead to unusual or poor results. By applying a quantitative steric assessment of the substituents at the 3,3′ positions of the binaphthol ring, we have systematically studied the effect of modulating this group on enantioselectivity for a wide range of reactions involving imines, and verified this analysis using ONIOM calculations. We have shown that in most reactions, the stereochemical outcome depends on both proximal and remote sterics. Summarising detailed calculations into a simple qualitative model identifies and explains the steric features required for high selectivity. This model is consistent with seventy seven papers reporting reactions (over 1000 transformations in total), and provides a straightforward decision tree for selecting the best catalyst. [ABSTRACT FROM AUTHOR]

Introduction of heterocycles into the helical skeleton of helicenes allows modulation of their redox, chiroptical, and photophysical properties. This paper describes the straightforward preparation and structural characterization by single-crystal X-ray diffraction of thiadiazole-[7]helicene, which was resolved into M and P enantiomers by chiral HPLC, together with its S-shaped double [4]helicene isomer, as well as the smaller congeners thiadiazole-[5]helicene and benzothiadiazole-anthracene. A copper(II) complex with two thiadiazole-[5]helicene ligands was structurally characterized, and it shows the presence of both M and P isomers coordinated to the metal center. The emission properties of the heterohelicenes are highly dependent on the helical turn, as the [7]- and [5]helicene are poorly emissive, whereas their isomers, that is, the S-shaped double [4]helicene and thiadiazole-benzanthracene, are luminescent, with quantum efficiencies of 5.4 and 6.5 %, respectively. DFT calculations suggest quenching of the luminescence of enantiopure [7]helicenes through an intersystem-crossing mechanism arising from the relaxed excited S1 state. [ABSTRACT FROM AUTHOR]

This paper describes the synthesis of both polysubstituted oxazolo-pyrrolidinones and -piperidinones by a domino process. The methodology is based on the reaction between hydroxyl halogenoamides and Michael acceptors, which leads efficiently to bicyclic lactams. The process is compatible with unsymmetrical electron-withdrawing groups on the Michael acceptor, which allows the formation of two contiguous and fully controlled tertiary and quaternary stereocenters. In the case of tetrasubstituted Michael acceptors, two adjacent quaternary stereocenters are formed in good yield. Starting from ( R)-phenylglycinol derived amides results in the formation of enantioenriched bicyclic lactams in low to good yields and with high levels of stereoselectivity, thus greatly increasing the scope and interest of this strategy. The origins of chirality transfer and diastereoselectivity were studied by DFT calculations and have been attributed to a kinetic control in one of the last two steps of the reaction sequence. This selectivity is dependent upon both the substituents on the Michael acceptor and the sodium cation chelation. [ABSTRACT FROM AUTHOR]

In this paper, we describe for the first time the synthesis of new chiral nanosized metal oxide surfaces based on chiral self-assembled monolayers (SAMs) coated with metal oxide (TiO2) nanolayers. In this new type of nanosize chiral surface, the metal oxide nanolayers enable the protection of the chiral self-assembled monolayers while preserving their enantioselective nature. The chiral nature of the SAM/TiO2 films was characterized by variety of unique techniques, such as second-harmonic generation circular dichroism (SHG-CD), quartz crystal microbalance, and chiral adsorption measurements with circular dichroism spectroscopy. The chiral resolution abilities of the SAMs coated with metal oxide (TiO2) nanolayers were investigated in the crystallization of a racemic mixture of threonine and glutamic acid. Our proposed methodology for the preparation of nanoscale chiral surfaces described in this article could open up opportunities in other fields of chemistry, such as chiral catalysis. [ABSTRACT FROM AUTHOR]

Knowledge about the active conformation of an asymmetric catalyst is highly valuable in order to understand its stereo‐inductive power, but spectroscopic access to these structures is often limited. This work showcases the application of vibrational CD spectroscopy to reveal the binding geometries of hydrogen‐bonding adducts of Takemoto's catalyst with five carboxylic acids. It was found that popular dispersion corrected DFT functionals to yield wrong structures for some of the adducts and that the characteristic VCD spectral signatures of the hydrogen‐bonded complexes are particularly helpful in identifying and correcting the wrongly predicted geometries. More information can be found in the Full Paper by C. Merten and N. M. Kreienborg on page 17948. [ABSTRACT FROM AUTHOR]

Rhodium(I) floating between the five nitrogen atoms of sapphyrin and how this affects chirality of the corresponding complex are depicted in the cover image. In addition, this work focuses on the CF3‐stabilized derivative and its ability to catalyze cyclopropanation. More information can be found in the Full Paper by Z. Gross et al. on page 17255. [ABSTRACT FROM AUTHOR]

A Chiral‐at‐Al aluminate can be prepared by the stepwise reaction of two different alcohols with the aluminate anion [EtAl(6‐Me‐2‐py)3]−. The method can also be used to prepare chiral‐at‐ligand aluminates and for the introduction of 3‐py and 4‐py functionalities into the aluminate framework through the selective and controlled substitution of one or two pyridine arms, thereby giving entry to new supramolecular chemistry. The cover represents the formation of such a rare example of a chiral‐at‐aluminum aluminate and it is also a tribute to the oneiric worlds of surrealist painter René Magritte. More information can be found in the Full Paper by R. García‐Rodríguez et al. on page 17019. [ABSTRACT FROM AUTHOR]

The chiral stereoisomers of new non‐ionic dendritic amphiphiles self‐assemble in aqueous solution towards helical ribbons with opposite handedness. However, in the case of the meso‐compound, cylindrical assemblies are observed, as illustrated. Modelling suggests that they consist of right‐ or left‐handed helical molecular strands in equal distribution. The hydrophobic core of such a cylinder is sized to accommodate the hydrophobic tails. Only the head groups and the aromatic platforms, which contribute high density in transmission electron microscopy (TEM), are shown for clarity. The paper discusses stereochemical aspects upon supramolecular assembly of these new dendritic amphiphiles. More information can be found in the Full Paper by C. Böttcher, et al. on page 5629 ff. [ABSTRACT FROM AUTHOR]

This work shows that the intuitive assumption of the sterically less hindered amide group being solvated preferentially does not hold for the cases of two 2,6‐pyridinediyl‐dialkylamides. Using vibrational circular dichroism (VCD) spectroscopy, solvation is found to induce significant conformational changes, which are not immediately apparent from 1H NMR data. More information can be found in the Full Paper by D. P. Demarque and C. Merten on page 17915. [ABSTRACT FROM AUTHOR]

The synthesis of molecular propellers featuring low ‐ energy activation barriers of the racemization reaction remains elusive. The trimerization reaction of enantiomerically ‐ pure binaphthols with hexakis(bromomethyl)benzene enabled the one ‐ step preparation of enantiomerically ‐ pure molecular propellers, in which three binaphthyl rings are held together through dioxecine rings. X ‐ ray diffraction analysis revealed that the six naphthyl moieties adopt a folded conformation, which shows a striking similarity to the mythological Sicilian symbol of Trinacria. More information can be found in the Full Paper by D. Bonifazi et al. on page 15348. [ABSTRACT FROM AUTHOR]

A moderately concentrated solution of a helically chiral polyisonitrile forms a stable two‐phase system in CDCl3 with the dense phase being close to isotropic and the less dense layer forming a completely anisotropic lyotropic liquid crystalline phase. This enables the enantiodifferentiating measurement of isotropic and anisotropic NMR parameters from a single sample by novel spatially resolved NMR methods. More information can be found in the Full Paper by M. Reggelin, B. Luy et al. on page 13351. [ABSTRACT FROM AUTHOR]

The cover image compares the molecular spin states of two diastereomers of a spin‐crossover iron(II) complex. Solution‐phase magnetic measurements show the low‐spin state of the heterochiral (meso) diastereomer is stabilized relative to its homochiral (rac) congener. This reflects a steric clash between phenyl substituents in the rac isomer, which occupies two diagonal quadrants in the molecule. The resultant twisting of the ligand conformation and metal‐coordination sphere explains the observed reduction in the ligand field. More information can be found in the Full Paper by M. A. Halcrow et al. on page 9067. [ABSTRACT FROM AUTHOR]

Planar chiral 4,7,12,15 ‐ tetrasubstituted [2.2]paracyclophane scaffolds stacked two AIE ‐ active monomers in close proximity at a chiral position. The resulting dimer exhibited strong emission even in a diluted solution by the suppression of the molecular motion. In particular, this binding effect could be readily released by heating. As a result, drastic changes in luminescent behavior were observed around room temperature regions. The dimers also showed excellent circular dichroism (CD) and circularly polarized luminescence (CPL) profiles. More information can be found in the Full Paper by M. Gon, Y. Morisaki and Y. Chujo on page 6323 ff. [ABSTRACT FROM AUTHOR]

Axially chiral BODIPY DYEmers display intense fluorescence and circularly polarized luminescence (CPL) spectra. Due to exciton coupling between the BODIPY rings the π* states split into two energy levels, giving strong ECD couplets. The strongly emitting excited state is the low ‐ lying exciton ‐ coupled level. TD ‐ DFT and CC2 calculations elucidated the photophysics behind the CPL of these systems. More information can be found in the Full Paper by M. Bröring, L. Di Bari, G. Pescitelli et al. on page 16089 ff. [ABSTRACT FROM AUTHOR]

Bistable Switches Four overcrowded alkENes have beEN synthesized and investigated experimENtally and computationally. Irradiation with UV light allowed high ‐ yielding E–Z isomerizations providing metastable diastereoisomers. Kinetic studies on metastable 1–4 using CD and HPLC idENtified two pathways at high temperatures for thermal isomerization. To show the value of these overcrowded alkENes as bistable switches, photochemical switching cycles were performed, which proved the alkENes to be excellENt switches. These favorable switching properties offer attractive prospects for the design of novel photoresponsive systems. For more details see the Full Paper by B. L. Feringa et al. on page 13478 ff. [ABSTRACT FROM AUTHOR]

The racemate of an inherently chiral “spider ‐ like” octathiophene monomer T83, in which chirality is generated by torsion in its backbone, was synthesized. In the cover image, the (S) ‐ T83 has woven a highly selective chiral web in which enantiomorphic insects (l ‐ and d ‐ DOPA, R ‐ and S ‐ FcA) are differently entrapped. More information can be found in the Full Paper by P. R. Mussini, T. Benincori, R. Martinazzo et al. on page 10839. [ABSTRACT FROM AUTHOR]

Optically active dendrimers, containing a planar chiral [2.2]paracyclophane as the X ‐ shaped core unit, were synthesized. Gram ‐ scale optical resolution and transformations of 4,7,12,15 ‐ tetrasubstituted [2.2]paracyclophanes were also carried out. The high ‐ generation dendrons effectively absorbed UV light and transferred the energy to the core, resulting in high photoluminescence from the core. In addition, the dendrons sufficiently isolated the emissive X ‐ shaped core, and intense circularly polarized luminescence was observed from thin dendrimer films. More information can be found in the Full Paper by Y. Morisaki, Y. Chujo et al. on page 2291 ff. [ABSTRACT FROM AUTHOR]

Invited for the cover of this issue is Yasuhiro Morisaki at Kwansei Gakuin University together with the group of Yoshiki Chujo at Kyoto University. The image depicts the circularly polarized luminescence of the dendrimer films described in their Full Paper. Read the full text of the article at . [ABSTRACT FROM AUTHOR]

Subporphyrins­ B ‐ Methoxy and B ‐ phenyl β ‐ sulfinylsubporphyrins have been separated into their diastereomers and their diastereomeric interconversions have been studied in various solvents, as reported by K. Yoshida and A. Osuka in their Full Paper on page 11727 ff. Diastereomeric interconversion of B ‐ methoxy subporphyrin diastereomers takes place in protic solvents as the first experimental observation of bowl inversion of a subporphyrin, which likely proceeds by an SN1 ‐ type mechanism via a subporphyrin borenium cation. [ABSTRACT FROM AUTHOR]

A rare, perfect case of a highly selective regiodivergent reaction of a racemic mixture is presented. Upon interaction with the Pd – (S,S) ‐ NHC catalyst (NHC=N ‐ heterocyclic carbene), the R enantiomer takes the right fork and the S enantiomer the left one. Thus, the racemic mixture reacts to give two regioisomeric enantiopure products. In this reaction a methyl CH activation competes with an asymmetric CH ‐ bond activation in a methylene unit to give single enantiomers of substituted indolines. DFT was the tool to map out the course of the reaction and to extend and rationalize the outcome. For more details see the Full Paper by E. P. Kündig et al. on page 15021 ff. [ABSTRACT FROM AUTHOR]

The twisting motion of 3,3‐bis(diphenylphosphoryl)‐2,2‐bipyridine (BIPYPO) provides s‐cis and s‐trans geometries of a chiral EuIII complex containing tris[3‐(trifluoromethylhydroxymethylene)‐(+)‐camphorate], inducing the sign inversion of the negative circularly polarized luminescence (CPL) signals at the 5D0→7F1 transition of EuIII. For more details see the Full Paper by J. Yuasa, H. Ueno, and T. Kawai on page 8621 ff. [ABSTRACT FROM AUTHOR]

Advanced graph set analysis has been proposed by incorporating a concept of symmetry into conventional graph set analysis. Based on the advanced graph set analysis, handedness determinations were demonstrated on supramolecular hidden chirality of three types of hydrogen‐bonded networks, 0D‐cubic, 1D‐ladder, and 2D‐sheet networks, by characterizing the symmetric properties of their component ring‐type hydrogen‐bonded networks formed by primary ammonium carboxylates. For more details see the Full Paper by I. Hisaki, M. Miyata et al. on page 2478 ff. [ABSTRACT FROM AUTHOR]

Expanded porphyrins The synthesis of the long sought‐after pyrazole‐based expanded porphyrin and its homobimetallic nickel(II) and copper(II) complexes is described in the Full Paper by G. Bringmann, C. Brückner, F. Meyer et al. on page 5868 ff. Spectroscopic evidence, as well as structural parameters of this hexaphyrin analogue (named the Siamese‐twin porphyrin), proved it to be non‐aromatic, though each half of the molecule is fully conjugated. In the complexes, each metal ion is coordinated in a square‐planar fashion by a dianionic, porphyrin‐like {N4} binding pocket. The conformations of the diprotonated macrocycle and its metal complexes are all strongly twisted. The persistent helical twist permitted resolution of the enantiomeric helimers by HPLC on a chiral phase. [ABSTRACT FROM AUTHOR]