Click Functionalization of a Dibenzocyclooctyne-Containing Conjugated Polyimine

• Published in: Angewandte Chemie International Edition Vol. 55; no. 3; pp. 945 - 949
• Main Authors: Kardelis, Vladimir, Chadwick, Ryan C., Adronov, Alex
• Format: Journal Article
• Language: English
• Published: WEINHEIM Blackwell Publishing Ltd 18.01.2016; Wiley; Wiley Subscription Services, Inc
• Edition: International ed. in English
• Subjects: Alkynes; Backbone; Chains (polymeric); Chemical synthesis; Chemistry; Chemistry, Multidisciplinary; click chemistry; conjugated polymers; Copolymers; Cycloaddition; Degree of polymerization; Density; Graft copolymers; Kinetics; Libraries; Molecular weight; Physical Sciences; Polyazomethines; Polyethylene glycol; Polyethylenes; polymer modification; Polymerization; Polymers; Polystyrene; Polystyrene resins; Science & Technology; AZA-WITTIG POLYMERIZATION; graft copolymers; COMPLEXES; polymer modification; click chemistry; WALLED CARBON NANOTUBES; ORGANIC POLYMERS; LIGHT-EMITTING-DIODES; DENSITY; CYCLOADDITIONS; CYCLOOCTYNE; DEVICES; polymers; DERIVATIVES; conjugated polymers
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201508639

A conjugated poly(phenyl‐co‐dibenzocyclooctyne) Schiff‐base polymer, prepared through polycondensation of dibenzocyclooctyne bisamine (DIBO‐(NH2)2) with bis(hexadecyloxy)phenyldialdehyde, is reported. The resulting polymer, which has a high molecular weight (Mn>30 kDa, Mw>60 kDa), undergoes efficient strain‐promoted alkyne–azide cycloaddition reactions with a series of azides. This enables quantitative modification of each repeat unit within the polymer backbone and the rapid synthesis of a conjugated polymer library with widely different substituents but a consistent degree of polymerization (DP). Kinetic studies show a second‐order reaction rate constant that is consistent with monomeric dibenzocyclooctynes. Grafting with azide‐terminated polystyrene and polyethylene glycol monomethyl ether chains of varying molecular weight resulted in the efficient syntheses of a series of graft copolymers with a conjugated backbone and maximal graft density. Click on a stick: Incorporation of a strained cyclooctyne monomer unit within the backbone of a conjugated polymer structure was achieved through Schiff‐base polymerization, thereby resulting in a conjugated polymer backbone that could be subsequently modified with a variety of azide derivatives through strain‐promoted azide–alkyne cycloaddition.