Noncovalent interactions within 3D molecular structure of diastereoisomers: A background for stereodependent redox activity

Highlights: • Noncovalent interactions influence electrochemical behavior of diastereomeric couples. • Noncovalent interactions trigger stereoelectronic differences in diastereomers. • Stereoelectronic interactions influence thermodynamics of electrochemical process. • Stereoelectronic interactions influence kinetics of electrochemical process. • New mechanism of stereo-dependent redox activity is revealed. -- Abstract: It was shown that noncovalent interactions within the 3D molecular structure can significantly influence thermodynamics and/or kinetics of electrochemical processes for either diastereomer creating background for electrochemical stereorecognition. The diastereomeric Schiff-base complexes derived from (S)-2-[N-(N′-benzylprolyl)amino] benzophenone and amino acids (serine and threonine) constitute interesting examples of electrochemical discrimination in the metal complexes which is not attributed to the distortion of coordination polyhedra of the metal center in the one of stereoisomers, as it has been actualized in the previously reported data. The results obtained demonstrate that even peripheral groups in the metal coordination environment can play an important role influencing the relative impact of different parts of molecule in the frontier orbitals via conformational changes. The origin of a new mechanism of stereo-dependent redox activity was established using quantum chemical calculations. The examples discussed will be useful for targeted molecular design of new chiral redox active materials for electrochemical enantio recognition.