An amphiphilic pseudo[1]catenane: neutral guest-induced clouding point change

作者：Ogoshi Tomoki^*; Akutsu Tomohiro^*; Yamagishi Tada aki^*

来源：Beilstein Journal of Organic Chemistry, 2018, 14: 1937-1943.

DOI：10.3762/bjoc.14.167

• amphiphilic molecules
• host-guest complexes
• lower critical solution temperature
• pillar[n]arenes
• pseudo[1]catenane

The hydrophobic/hydrophilic ratio in a molecule largely affects its assembled properties in aqueous media. In this study, we synthesized a new bicyclic compound which could dynamically change its hydrophobic/hydrophilic ratio by chemical stimulus. The bicyclic compound consisted of amphiphilic pillar[5]arene and hydrophobic alkyl chain rings, and formed a self-inclusion structure in aqueous media, which was assigned as a pseudo[l]catenane structure. The hydrophobic chain ring was hidden inside the pillar[5]arene cavity in the pseudo[l]catenane structure, thus the bicyclic compound was soluble in water at 20 degrees C with a clouding point at 24 degrees C. The pseudo[l]catenane was converted to the de-threaded structure upon addition of the neutral guest 1,4-dicyanobutane, which displaced the alkyl chain ringg from theinmside to the outside of the cavity The hydrophobic alkyl chain ring was now exposed to the aqueous media, causing aggregation of the hydrophobic alkyl chain rings, which inducedinmsolubilization of the bicyclic compoundinm aqueous media at 20 degrees degrees C and a decreaseinm its clouding poin.t

• 出版日期2018-7-26