Mechanophore activation enhanced by hydrogen bonding of diarylurea motifs:An efficient supramolecular force-transducing system

作     者：Jumpei Kida Daisuke Aoki Hideyuki Otsuka 

作者机构：Department of Chemical Science and EngineeringTokyo Institute of TechnologyMeguro-kuTokyoJapan 

出 版 物：《Aggregate》 (聚集体（英文）)

年 卷 期：2021年第2卷第3期

页      面：9-13页

核心收录：

学科分类：07[理学] 070303[理学-有机化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 

基　　金：supported by KAKENHI grant 17H01205 (Hideyuki Otsuka)from the Japan Society for the Promotion of Science (JSPS) by JST CREST grant JPMJCR1991 (Japan) support from a JSPS Research Fellowship for Young Scientists (201914764). 

主　　题：hydrogen bonding mechanophore radical 

摘      要：Macromolecules are efficient as mechanical transducers for mechanically induced chemical bond cleavage reactions.Although various classes of polymers have been studied as effective mechanical-force transducers for mechanophores,alternatives to polymer chains,that is,small molecules,have rarely been studied.In this paper,the role of hydrogen bonding as small-molecule mechanical-force transducers for the activation of mechano-responsive molecular units(mechanophores)in the bulk is investigated.The introduction of diarylurea linkage motifs,which are known as strong hydrogen bonding groups,enhances the mechanochemical activation of the fluorescent mechanophore tetraarylsuccinonitrile(TASN)as effectively as the attachment of a typical macromolecular transducer.Electron paramagnetic resonance measurements of mechanically activated TASN with diphenyl urea motifs demonstrate its higher carbon–carbon bond dissociation ratio compared to that of TASN without diphenyl urea motifs.This efficient supramolecular-forcetransducing system represents a new concept in the field of mechanochemistry,namely,the enhancement of mechanochemical bond scission by simply changing the substituents of a mechanophore,even in small molecules.