The use of calixarenes in asymmetric catalysis is receiving increasing attention due to their tunable three-dimensional molecular platforms along with their easy syntheses and versatile modification at the upper and lower rims. This review summarizes the recent progress of synthesis and use of chiral calixarenes in asymmetric syntheses which emerged later than 2010.

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A new chiral calix[4]arene-based organocatalyst 3 bearing bis-squaramide moieties was designed and synthesized from p-tert-butylcalix[4]arene. This bifunctional organocatalyst was used in the enantioselective conjugate addition of acetyl acetone to β-nitrostyrenes. The corresponding adducts were obtained in good to excellent yields with high enantioselectivities.

Typical congeners of the boron Lewis acid tris(pentafluorophenyl)borane, B(C 6 F 5 ) 3 , are fluorinated at the aryl groups directly attached to the boron atom. The chemistry of related electron-deficient boranes with fluorination distal to the Lewis acidic center is largely unexplored. The preparation and characterization of tris(5,6,7,8tetrafluoronaphthalen-2-yl)borane are reported. It serves as a model system that provides sites for further substitution at C-1 and C-3 of the naphthalen-2-yl units. A Gutmann− Beckett analysis of its Lewis acidity revealed that, despite remote fluorination, it is as Lewis acidic as B(C 6 F 5 ) 3 . The new Lewis acid performs equally well in CO and CN reduction as well as dehydrogenative Si−O coupling involving Si−H bond activation. Adducts with water and a phosphine oxide are crystallographically characterized.

The purpose of this study was to investigate the cognitive structures of chemistry teacher candidates about "stereochemistry". A case study research method, one of the qualitative research patterns, was used in the study and the sample of study involved 28 prospective chemistry teachers who had taken Organic Chemistry I and II courses at Education Faculty of a middle Anatolian university. For the data collection, stereochemistry concept inventory comprising of 20 questions was used. In the analysis of data, students' responses in SCI were categorized. The detailed analysis of the results indicated that chemistry teacher candidates had some misconceptions concerning stereochemistry parallel to the literature. Based on these observations, some suggestions were presented for improving students' foundational understanding about stereochemistry.