A Heteroatom‐Containing Functional Poly(Silylenevinylene): Synthesis, Anion Binding, and Sensing of Anion Extraction Processes

Catalytic hydrosilylation is one of the important synthetic approaches to prepare functional organosilicon polymers. Herein, a functional silicon copolymer is constructed by polyhydrosilylation reaction between a novel 3,7‐bis(dimethyl silane)‐10‐(2‐ethylhexyl)‐10H‐phenothiazine monomer and a neutral tetrapyrrolic macrocycle, namely, 5,5,10,15,15,20‐hexamethyl‐10α, 20α‐bis(4‐[ethynylphenyl]) calix[4]pyrrole. The as‐constructed copolymer (Mn = 9609, PDI = 2.2) is investigated as an extractant for organic anions as their tetrabutylammonium salts under interfacial aqueous‐organic (water‐chloroform) conditions. In this context, a distinctive naked‐eye colorimetric as well as fluorescence detection method is developed based on anion‐directed hydrogen‐bonding interactions. This kind of color/fluorescence monitoring serves as a handy tool for rapid screening of anion extraction processes. The copolymer exhibits high selectivity toward extraction of chloride anion. This study augments the field of polycarbosilanes, poly(silylenevinylene)s in particular, allowing access to a new application window that can be further advanced with good grace in near future. A bona fide poly(silylenevinylene) having an isomeric and conformationally flexible porphyrinogen is developed. The copolymer can effectively bind smaller halides as evidenced by proton NMR spectroscopy. An unprecedented naked‐eye dual optical sensing paradigm is formulated, which showcases the effectiveness of the copolymer in the selective extraction of chloride anion from aqueous solution.