Angewandte Chemie International Edition

Chang, Julia J.; Du, Chuanshen; Pauls, Alana; Thuo, Martin

doi: 10.1002/anie.202182562pmid: N/A

Chuang, Hsiang‐Yu; Schupp, Manuel; Meyrelles, Ricardo; Maryasin, Boris; Maulide, Nuno

doi: 10.1002/anie.202182561pmid: N/A

Dubey, Abhinav; Stoyanov, Nikolay; Viennet, Thibault; Chhabra, Sandeep; Elter, Shantha; Borggräfe, Jan; Viegas, Aldino; Nowak, Radosław P.; Burdzhiev, Nikola; Petrov, Ognyan; Fischer, Eric S.; Etzkorn, Manuel; Gelev, Vladimir; Arthanari, Haribabu

Filez, Matthias; Vesely, Martin; Garcia‐Torregrosa, Ivan; Gambino, Marianna; Attila, Özgün; Meirer, Florian; Katrukha, Eugene A.; Roeffaers, Maarten B. J.; Garrevoet, Jan; Kapitein, Lukas C.; Weckhuysen, Bert M.

doi: 10.1002/anie.202182511pmid: N/A

Kopinke, Frank‐Dieter

doi: 10.1002/anie.202100231pmid: 33977621

Vercammen, Jannick; De Vos, Dirk

doi: 10.1002/anie.202105139pmid: 33977615

Ghosh, Arghya; Biju, Akkattu T.

doi: 10.1002/anie.202012581pmid: 33205860

The secondary amine‐catalyzed reactions proceeding via α,β‐unsaturated iminiums and the N‐heterocyclic carbene (NHC)‐catalyzed transformations taking place via α,β‐unsaturated acylazoliums are the two widely used electrophilic intermediates in organocatalysis. Over the last two decades, these two intermediates are extensively utilized for the enantioselective construction of valuable molecules. Both intermediates are generated by the covalent binding of catalysts to the substrates leading to LUMO activation of α,β‐unsaturated carbonyls. A variety of soft nucleophiles are known to add to the α,β‐unsaturated iminiums and acylazoliums in a conjugate fashion, and in many cases, striking similarity in reactivity has been observed. Having said this, there are few cases where these intermediates exhibit difference in reactivity. This Minireview is aimed at highlighting the resemblances in reactivity between α,β‐unsaturated iminiums and acylazoliums thereby shedding light on the unnoticed parallels of the two intermediates in organocatalysis.

Wemyss, Alan M; Ellingford, Christopher; Morishita, Yoshihiro; Bowen, Chris; Wan, Chaoying

doi: 10.1002/anie.202013254pmid: 33411416

While the fascinating field of soft machines has grown rapidly over the last two decades, the materials they are constructed from have remained largely unchanged during this time. Parallel activities have led to significant advances in the field of dynamic polymer networks, leading to the design of three‐dimensionally cross‐linked polymeric materials that are able to adapt and transform through stimuli‐induced bond exchange. Recent work has begun to merge these two fields of research by incorporating the stimuli‐responsive properties of dynamic polymer networks into soft machine components. These include dielectric elastomers, stretchable electrodes, nanogenerators, and energy storage devices. In this Minireview, we outline recent progress made in this emerging research area and discuss future directions for the field.

Kajetanowicz, Anna; Grela, Karol

doi: 10.1002/anie.202008150pmid: 32808704

Advanced applications of the Nobel Prize winning olefin metathesis reaction require user‐friendly and highly universal catalysts. From many successful metathesis catalysts, which belong to the two distinct classes of Schrock and Grubbs‐type catalysts, the subclass of chelating‐benzylidene ruthenium complexes (so‐called Hoveyda–Grubbs catalysts) additionally activated by electron‐withdrawing groups (EWGs) provides a highly tunable platform. In the Review, the origin of the EWG‐activation concept and selected applications of the resulting catalysts in target‐oriented synthesis, medicinal chemistry, as well as in the preparation of fine‐chemicals and in materials chemistry is discussed. Based on the examples, some suggestions for end‐users regarding minimization of catalyst loading, selectivity control, and general optimization of the olefin metathesis reaction are provided.