Electrocarboxylation of Spiropyran Switches through Carbon-Bromide Bond Cleavage Reaction

Abstract

This manuscript deals with carbon capture and utilization to synthetize high-added chemicals using CO2 as a C1-organic building block for C−C bond formation. The study focuses on the electrocarboxylation of 1,3,3-trimethylindolino-6′-bromobenzopyrylospiran switch (Br-BIPS). Prior to the electrocarboxylation process, the electrochemical reduction mechanism of Br-BIPS and CO2 is disclosed in polar aprotic solvents using two different cathodes (glassy carbon and silver) under nitrogen atmosphere. Once the role of the cathode in the reduction carbon-bromide bond cleavage is understood, carboxylated spiropyran derivatives can be synthesized in moderate yields and conversion rates through an electrocarboxylation process using CO2 silver cathode and polar aprotic solvents. The “green” efficient route described in the current work would open a new sustainable strategy for designing and building “smart” surfaces with switchable physical properties.