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Enallenylamides have been utilized for the synthesis of heterobicycle[4.2.0]octane derivatives via Ir/hν promoted [2+2] cycloaddition reaction. The reaction specifically targets the distal double bond of the allene moiety, and results in the exclusive formation of the trans product. The process is conducted at room temperature and under an inert atmosphere. An extensive study on the substituent propensities during the cycloaddition step revealed variable effects. Electron‐withdrawing groups conjugated with the double bond participating in the cycloaddition either hindered the process or reduced its yield. Conversely, electron‐donating substituents enhanced the efficiency, resulting in product yields ranging from 60% to 88%. Our study also demonstrated the influence of protecting groups on the reaction pathway. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of four dumbbell‐shaped fullerene molecules connected by isosorbide and isomannide moieties is presented. Additionally, their electrochemical behavior and their ability to form complexes with [10]cycloparaphenylene ([10]CPP) were investigated. The cyclic voltammetry (CV) results of the fullerene dumbbells demonstrate a high electron affinity, indicating their strong interaction with electron‐donating counterparts such as carbon nanorings, which possess complementary charge and shape properties. To study the thermodynamic and kinetic parameters of complexation, isothermal titration calorimetry (ITC) was employed. NMR titration experiments provided further insights into the binding stoichiometries. Two distinct approaches were utilized to create bridged structures: one based on cyclopropane and the other based on furan. Regardless of the type of linker used, all derivatives formed conventional 2 : 1 complexes denoted as [10]CPP2⊃C60derivative. However, the methano‐dumbbell molecules exhibited distinct binding behavior, resulting in the formation of mono‐ and bis‐pseudorotaxanes, as well as oligomers (polymers). The formation of linear polymers holds significant potential for applications in solar energy conversion processes. [ABSTRACT FROM AUTHOR]

A photochemically promoted intramolecular cyclization of aryl‐, vinyl‐, and alkyliodo allenes has been developed. The optimal conditions employed [Ir(ppy)2(dtbbpy)]PF6 (1 mol%) as catalyst affording products with high exo selectivity in moderate to good yields. Chiral substrates showed diastereoselectivity of up to 95/5 favoring trans product. [ABSTRACT FROM AUTHOR]

Summary: In the present work, we describe the chemical synthesis of 3‐HFAs as prominent derivatives of fatty acids and assess if they could be applied as phase change materials (PCM). In addition, 3‐HFAs were obtained by depolymerization of a bacterial biopolymeric material, polyhydroxyalkanoate. Thermal properties of 3‐hydoxyoctanoic, decanoic, and dodecanoic acids are reported for the first time. These materials showed the potential to be applied as PCM in temperature range from 33°C to 66°C. In order to expand the temperature range for application of 3‐HFAs as PCM, eutectic mass ratios of three kinds of binary mixtures of 3‐HFAs were calculated, and their properties were predicted using the Schröder‐van Laar equation. Thermal properties of these mixtures were validated by differential scanning calorimetry (DSC) analysis. These results showed that eutectics considerably expanded the scope of applications of 3‐HFAs as PCMs. 3‐HFAs originating from biotechnologically obtained polyhydroxyalkanoates also showed potential to be applied in development of PCMs. [ABSTRACT FROM AUTHOR]

Additionally, the artwork highlights the formation of methano-dumbbell oligomers, emphasizing their potential application in sustainable solar energy conversion. Cover Feature: Sugar-Bridged Fullerene Dumbbells and Their Interaction with the [10]Cycloparaphenylene Nanoring (Chem. Eur. J. 44/2023) Keywords: dumbbells; fullerenes; isomannides; isosorbides; pseudorotaxanes EN dumbbells fullerenes isomannides isosorbides pseudorotaxanes 1 1 1 08/09/23 20230804 NES 230804 B The cover picture represents b the fascinating interaction between novel sugar-bridged fullerene dumbbells and the [10]cycloparaphenylene nanoring. [Extracted from the article]