Acid/Base‐Sensitive Ring‐Opening Metathesis Polymers Based on Phenanthroimidazole Dyes

Abstract

Poly(norbornenes) with pendant 2‐phenyl‐1H‐phenanthro[9,10‐d]imidazole in different ratios were prepared and their photophysical properties were studied in the presence and absence of acids. The polymers exhibited good film‐forming properties, which paved the way to study their acid/base‐sensitivity in the solid state. Polymer films with a high fluorophore content exhibited self‐absorption in their non‐protonated form and a pronounced fluorescence response in the presence of gaseous HCl. In contrast, thin films of the polymer with a low dye content showed almost no self‐absorption and only a poor response to the acidic analyte.magnified image

Dye-functionalized polymers via ring opening metathesis polymerization: principal routes and applications

“…Polynorbornenes with pendant 2-phenyl-1H-phenanthro[9,10-d]imidazoles showed a profound change of the photoluminescence of films upon exposure to HCl vapor [30,31]. Furthermore, xanthene functionalized [via copolymerization of fluorescein, dichlorofluorescein, and eosin-bearing monomers (6)] ROMP polymers showed acid/base sensitive behavior when neat films were exposed to HCl or trimethylamine vapors, which makes them promising materials for sensing applications [40].…”

“…[2.2.1]Bicyclohept-5-enederivatives (norbornenes) are the most common monomers in ROMP, as a huge variety of different monomers can be [15][16][17], pentacene [18], tetracene [18] Anthracene [15,17], pyrene [19], benzothienobenzothiophene [20] --Anthracene [74] Fluorene [90] (Hetero)cycles Perylene bisimides [21][22][23][24], hexabenzocoronene [25][26][27], quinolone [26], pyrene [29] Phenanthroimidazole [30,31] perylene bisimides [21], quinizarine [32], phenoxynaphthacene [33] Perylene bisimides [21] Phenanthroimidazole [11], perylene bisimides [8], pyrene [9] Coumarin [79] Benzoxazole [81] Benzoxazole [76,90] a Triphenylmethane dyes (Dichloro)fluorescein [40], eosin [40] Eosin [41] Oregon Green 488 [42], rhodamin B [43], rhodamin [44], fluorescein [44], eosin [45][46][47] Fluorescein [10] Rhodamin, [10,…”

“…A wide range of suitable monomers has been copolymerized comprising (hetero)polyaromatic compounds [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33], and more sophisticated functionalities like conjugated oligomers [34][35][36][37][38][39], triphenylmethane [40][41][42][43][44][45][46][47], azo [48][49][50][51][52], or polymethine [53][54][55][56][57] dyes. Even transition metal coordination compounds of aluminum [58,59], iron [60], zinc [61][62][63], ruthenium [64, 65], europium …”

Design and Synthesis of Some Imidazolyl Derivatives: Photophysical Studies and Application in the Detection of Anions

“…Phenanthroimidazole based systems due to the dramatic supramolecular properties, stability, ease of synthesis, a high extinction coefficient and tuneable photophysical properties have been explored as potential chromophores in a molecular-tweezers system for explosives [45], amine sensors [46,47], fluorophore in a super-radiant laser dye [48], fluorescent tag [49], OLED materials [50 -52] and chemosensors [53 -56]. The one-step synthesis of phenanthroimidazole derivatives has remarkably increased our own interest to involve a variety of aldehydes that may further extend the way for the introduction of other functionalities and to extend the conjugation for different purposes.…”

Synthetic and Physicochemical Aspects of Advanced Stimuli‐Responsive Polymers

“…Precisely controlled peptide-pendant copolymers [27] and amino acid functionalized norbornenes containing ester carboxy groups [28,29] are the prime examples. Taking advantage of the versatility of the ROMP process, bioactive and therapeutic polymers were also developed [30], including stimuli-responsive betaines [31] and acid-base sensitive phenanthroimidazole-based [32] and thiol-functional [33] polymers. In addition, notable synthesis of tunable, temperature-responsive polynobornenes with elastin peptide side chains was reported [34].…”