Pendent supported rare coordination for flavin: Structural, photophysical and morphological characterization of flavin-silver(I) complexes

Abstract

The present manuscript discusses our effort in stabilizing the rare bidentate coordinate mode for the flavin entity, via pendent supported secondary coordination; thereby resulting in a polymeric structure. Subtle chemical modification around the flavin core structure incorporating allyl and picolyl functionality in proximity to the secondary coordinate site was envisaged and two novel flavin analogues allylflavin (AF) and picolylflavin (PiF) was synthesized and solid-state X-ray diffraction studies was performed to elucidate the structural features of their silver complexes. Interestingly, two crystallographically unique silver ions was found to be characteristic feature, with different geometry around silver ion is observed depending on its involvement in coordination at primary or secondary site of the flavin unit. Furthermore, complexation behavior has been probed via photophysical techniques and morphological studies were undertaken to ascertain the facile transfer of the coordination polymeric motif onto the surface.