Dynamic covalent bonds (DCBs), which can undergo reversible cleavage and reformation upon exposure to readily useable stimuli, have attracted dramatic attention, but the library of such bonds still remains to be developed. Herein, we report molecular structures, dynamic behaviors, and healability of bis­(2,2,6,6-tetramethylpiperidin-1-yl)­trisulfide (BITEMPS-S3) to compare with its disulfide analogue (BITEMPS-S2) exchanged at moderate temperature. Unsymmetrical cleavage of trisulfide linkage induced relatively rapid disproportionation to di- and tetrasulfide derivatives. In the bulk, poly­(hexyl methacrylate) networks partially containing the BITEMPS-S3 moiety as a cross-linking point afforded nearly quantitative damage healability only by simple hot pressing at 110 °C under mild pressure. A slightly higher healability of BITEMPS-S2 compared to that of BITEMPS-S3 would be due to the differences in the chain-transfer reaction for the trisulfide linkage during free-radical polymerization rather than thermal exchangeability of the BITEMPS-S3 moiety. Therefore, not only BITEMPS-S2 but also BITEMPS-S3 should be regarded as one of DCBs triggered upon exposure to mild external stimuli.

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Supramolecular multilayered ferromagnets in which metal layers are interleaved with iminonitroxide benzoate radical anions have been synthesized and characterized by the authors. The structure of these novel compounds (see cover) consists of stacks of alternating organic–inorganic layers. Long‐range ferromagnetism is evidenced by magnetic and electroparamagnetic resonance (EPR) measurements, and shows clear interaction between the two sub‐networks. In this respect, this new class of hybrid magnets differs markedly from classical intercalated layer compounds.

This paper describes the synthesis of highly sterically hindered piperidinyl trisulfide with four spirocyclohexyl moieties, bis(2,6-bis[spirocyclohexyl]piperidine-1-yl)trisulfide (BIBSCPS-S3), from commercially available starting materials in short steps and its application as a...

For the synthesis of phenazasiline with various degree of polymerization, phenazasilinediboronic acid esters (B-Phz-Bs) were prepared. Each absorption λmax of B-Phz-Bs was observed at longer wavelength than that of corresponding dibromophenazasiline derivatives (Br-Phz-Br). Reactions of B-Phz-B with monobromophenazasiline and Br-Phz-Br gave terphenazasiline (Me-3Phz-Mes) and poly(phenazasiline) (PPhz), respectively. The optical and electrochemical properties of phenazasilines with various degrees of polymerization were also studied. The absorption λmax of the compound with higher degree of polymerization was observed at longer wavelength. Cyclic voltammetry (CV) of monophenazasiline showed a one-step reversible redox process. On the other hand, CVs of biphenazasiline and poly(phenazasiline) showed two-step reversible redox process and that of terphenazasiline showed three-step reversible redox process, respectively.