Threading of Conformationally Stable Calix[6]arene Wheels Substituted at the Methylene Bridges

Calix[6]arenes disubstituted at the methylene bridges, which are stable in the cone or 1,2,3-alternate conformation, form pseudorotaxanes with dialkylammonium axles. The cone wheel-based pseudorotaxanes are 10-100 times more stable than those obtained with the native conformationally mobile calix[6]arene wheel, as a consequence of their higher degree of preorganization. The threading of conformationally stable 1,2,3-alternate calix[6]arenes is unprecedented in the literature. Therefore, very peculiar NMR features are here evidenced for this threading process involving the less symmetrical 1,2,3-alternate calix[6]arene conformation, which implies a peculiar rototranslation motion of the axle

Nucleophilic Functionalization of the Calix[6]arene Para- and Meta-Position via p‑Bromodienone Route

It is here demonstrated that the p-bromodienone route, previously reported for calix[4]arenes, is also effective for the functionalization of the calix[6]arene macrocycle. Thus, alcoholic O-nucleophiles can be introduced at the calix[6]arene exo rim. In addition, the reaction of a calix[6]arene p-bromodienone derivative with an actived aromatic substrate, such as resorcinol, led to the first example of a meta-functionalized, inherently chiral calix[6]arene derivativ

Cross-linguistic and cognitive aspects in the acquisition of WH-questions in an Italian-Indonesian bilingual child

This chapter examines language development in a bilingual child growing up with two typologically distinct languages – Italian and Jakarta Indonesian. It presents a case study of unbalanced bilingualism and focuses on the development of WH-forms and concludes that dominance of the loose Indonesian syntactic pattern results in a non-target word order in the construction of early WH-questions in Italian. In conclusion, the chapter identifies cross-linguistic structures in quantitative and qualitative perspectives and hypothesizes theoretical explanations for cross-linguistic dominance and the gradual emergence of correct usage of Italian grammatical structures. In so doing, the study considers how children recognize languages as separate systems and how they gradually develop the cognitive patterns required for competence in separate though practically co-extensive linguistic domains