Protocol for aqueous synthesis of bioactive quaternary ammonium betaine derivatives under blue LED

Quaternary ammonium compounds exhibit diverse applications as antibiotics, as surfactants, in paper industries, in sewage treatment, and in aquaculture. Here, we present a protocol for synthesizing a library of bioactive quaternary ammonium betaine derivatives under blue LED in water. We describe steps for preparing diazo compounds, synthesizing glycine betaine derivatives, and isolating pure final compounds via precipitation from an aqueous reaction mixture. This protocol promotes a sustainable approach by using water as the reaction medium and room temperature reactions. For complete details on the use and execution of this protocol, please refer to Rath et al. (2023).1 [Display omitted] •Preparation of aryl diazo esters at room temperature•Blue LED mediated nitrogen insertion reaction•Purification by precipitation from aqueous solution•Analysis of the product by NMR and HRMS Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics. Quaternary ammonium compounds exhibit diverse applications as antibiotics, as surfactants, in paper industries, in sewage treatment, and in aquaculture. Here, we present a protocol for synthesizing a library of bioactive quaternary ammonium betaine derivatives under blue LED in water. We describe steps for preparing diazo compounds, synthesizing glycine betaine derivatives, and isolating pure final compounds via precipitation from an aqueous reaction mixture. This protocol promotes a sustainable approach by using water as the reaction medium and room temperature reactions.