Electropolymerization without an electric power supply

Toward Biomass-Based Organic Electronics: Continuous Flow Synthesis and Electropolymerization of N-Substituted Pyrroles

Pyrroles are foundational building blocks in a wide array of disciplines, including chemistry, pharmaceuticals, and materials science. Currently sourced from nonrenewable fossil sources, there is a strive to explore alternative and sustainable synthetic pathways to pyrroles utilizing renewable feedstocks. The utilization of biomass resources presents a compelling solution, particularly given that several key bulk and fine chemicals already originate from biomass. For instance, 2,5-dimethoxytetrahydrofuran and aniline are promising candidates for biomass-based chemical production. In this study, we present an innovative approach for synthesizing N-substituted pyrroles by modifying the Clauson-Kaas protocol, starting from 2,5-dimethoxytetrahydrofuran as the precursor. The developed methodology offers the advantage of producing pyrroles under mild reaction conditions with the potential for catalyst-free reactions depending upon the structural features of the substrate. We devised protocols suitable for both continuous flow and batch reactions, enabling the conversion of a wide range of anilines and sulfonamides into their respective N-substituted pyrroles with good to excellent yields. Moreover, we demonstrate the feasibility of depositing thin films of the corresponding polymers onto electrodes through in situ electropolymerization. This innovative application showcases the potential for sustainable, biomass-based organic electronics, thus, paving the way for environmentally friendly advancements in this field.

Bulk Electrosynthesis of Patchy Particles with Highly Controlled Asymmetric Features

Asymmetric modification of particles with various patches of different composition and size at predefined positions is an important challenge in contemporary surface chemistry, as such particles have numerous potential applications, ranging from materials science and (photo)catalysis to self-assembly and drug delivery. However, approaches allowing the synthesis of this kind of complex objects in the bulk of a solution in a straightforward way are currently lacking. In this context, bipolar electrochemistry (BE) is a powerful technique for the asymmetric modification of conducting objects. Herein, this approach is used for the highly controlled modification of particles with different metal patches, generated at specific locations of isotropic objects. The synthesis is carried out in the bulk of the solution and leads to predefined patterns of increasing complexity, including even a specific chiral arrangement of the patches.

Spiers Memorial Lecture: Old but new organic electrosynthesis: history and recent remarkable developments

Organic electrosynthesis has a long history. However, this chemistry is still new. Recently, we have seen its second renaissance with organic electrosynthesis being considered a typical green chemistry process. Therefore, a number of novel electrosynthetic methodologies have recently been developed. However, there are still many problems to be solved from a green and sustainable viewpoint. After an explanation of the historical survey of organic electrosynthesis, this paper focuses on recent remarkable developments in new electrosynthetic methodologies, such as novel electrodes, recyclable nonvolatile electrolytic solvents and recyclable supporting electrolytes, as well as new types of electrolytic flow cells. Furthermore, novel types of organic electrosynthetic reactions will be mentioned.

High-Throughput Electrosynthesis of Gradient Polypyrrole Film Using a Single-Electrode Electrochemical System

As an effective approach for materials synthesis, bipolar electrochemistry has been earning a renewed interest nowadays thanks to its unique features compared to conventional electrochemistry. Indeed, the wireless mode of electrode reactions and the generation of a gradient potential distribution above the bipolar electrode are among the most appealing qualities of bipolar electrochemistry. In particular, the gradient potential distribution is a highly attractive characteristic for the fabrication of surfaces with gradients in their chemical properties or molecular functionalities. Herein, we report the high-throughput electrosynthesis of gradient polypyrrole films by means of a new electrochemical cell design named the single-electrode electrochemical system (SEES). SEESs are made by attaching an inert plastic board with holes onto an indium tin oxide electrode, constructing multiple microelectrochemical cells on the same electrode. This type of arrangement enables parallel electrochemical reactions to be carried out simultaneously and controlled in a contactless manner by a single electrode. Several experimental conditions for polypyrrole film growth were extensively investigated. Furthermore, the gradient property of the polymer films was evaluated by thickness determination, surface morphology analysis, and contact angle measurements. The use of SEES has been demonstrated as a convenient and cost-effective strategy for high-throughput electrosynthesis and electroanalytical applications and has opened up a new door for gradient film preparation via a rapid condition screening process.