Homo- and heterochirality regulated blue and red phase polymerization of diacetylene with enantiomeric and racemic gelators

Abstract

Polydiacetylene (PDA) is a widely investigated polymer that shows unique blue and red phases. The precise control of the blue and red phase topochemical polymerization is an interesting topic. Here, we demonstrated that the supramolecular chirality of the gel matrix can selectively drive the monomeric diacetylene into blue and red phase. It was found that an amphiphilic diacetylene (PCDA) could form organogels with either l- or d-enantiomeric glutamide gelator and self-assembled into twisted ribbons. Upon photo irradiation of the gels, PCDA can be photopolymerized into PDA with blue color. However, when PCDA co-assembled with racemic gelators, PCDA was polymerized into red phase PDA. That is, homo- and heterochiral gelators lead the PCDA to be polymerized into blue and red phase, respectively. Interestingly, the blue-colored PDA were able to visually distinguish the arginine from the other amino acids via a blue to red color change.