The ability to synthesize complex organic molecules is essential to the discovery and manufacture of functional compounds, including small-molecule medicines. Despite advances in laboratory automation, the identification and development of synthetic routes remain a manual process and experimental synthesis platforms must be manually configured to suit the type of chemistry to be performed, requiring time and effort investment from expert chemists. The ideal automated synthesis platform would be capable of planning its own synthetic routes and executing them under conditions that facilitate scale-up to production goals. Individual elements of the chemical development process (design, route development, experimental configuration, and execution) have been streamlined in previous studies, but none has presented a path toward integration of computer-aided synthesis planning (CASP), expert refined chemical recipe generation, and robotically executed chemical synthesis.
Nitrosamines make up a major class of contaminants of emerging concern that are toxic, present at trace levels in aqueous environments, and challenging to destroy because of their chemical stability. We report novel redox electrodes based on hemin-functionalized carbon nanotubes showing high electrocatalytic activity for nitrosamine reduction at low potentials (−0.5 V vs Ag/AgCl or −0.27 vs the standard hydrogen electrode) and with turnover numbers of 700. The redox electrodes were tested under a range of electrolyte and pH conditions and demonstrated high conversion of nitrosamines at high reaction rates, even at parts per billion levels in secondary effluent from a wastewater treatment plant. We propose that the pathway for nitrosamine reduction involves a proton-mediated conversion of the nitroso group to hydrazines and secondary amines. These high-performance biomimetic electrocatalysts for nitrosamine reduction are based on complexes containing earth-abundant metals and, potentially, have broad applications in environmental remediation, water treatment, and industrial organo-electrochemical processes.