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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]

This paper reviews the present state of the catalytic enantioselective Reformatsky reaction. Advancements in asymmetric versions of this reaction have recently led to a considerable extension of its scope and applicability, principally due to the use of highly active chiral ligands and very specific reaction conditions. [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]

In this paper, both gyrotropy and chirality are introduced in some composite fin-line structures. The propagation characteristics are investigated using the generalized exponential technique in the spectral domain combined with Galerkin's method. These fin lines include symetrical unilateral and bilateral fin lines. Numerical calculations are performed so as to examine the combined effects of changing different variables associated with the operating frequency, slot width, gyrotropy, and chirality parameters on the dominant mode propagation constant or effective dielectric constant. It is shown that the influences of chirality are just diverse. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 25: 40–44, 2000. [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]

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]