Design and synthesis of a catalytically efficient metal-flavin complex toward aerobic sulphoxidation was achieved via judicially positioning the metal ion near the catalytic site thereby assisting the intermediate formation.

This Communication describes the formation of 1D-coordination polymeric motifs involving modified flavin analog connected together through intervening silver ions. Rare bidentate coordination mode for model flavin was achieved with silver...

The present manuscript describes the synthesis and the photophysical properties of a pair of novel flavin-pyrene dyads where the donor and the acceptor entities are separated via variable spacer. The dyads were well characterized using standard techniques and investigated for their photophysical and electrochemical nature. The observed absorption spectra of the dyads mainly display peaks corresponding to the individual pyrene and flavin units, with some contribution from the flavin entity in the pyrene region. While, strong emission quenching was observed for both the dyads if compared to its individual constituents. However, a careful analysis of the emission spectra and the solvent dependent studies reveals subtle difference between the two dyads. While no significant difference could be observed when excited in the flavin region; excitation at the pyrene region displays a weak and broad emission band in case of closely connected dyad. Further, the electrochemical properties were investigated by cyclic voltammetry and the reduction ability was observed to follow the trend as FlPy2 < FlPy1 < Fl.

Herein, we report the functionalization of the gold nanoparticles with pyrene fluorophore via a connecting nucleobase spacer displaying the inherent photoluminescence behavior, without getting quenched by the gold nanoparticle surface...

Herein we report solid state analysis of the silver-flavin complexes grown under different chemical environmentsneutral (complex 1), acidic (complex 2) and basic (complex 3) mediums. While preferred and frequently reported primary coordination is observed in all three cases; involvement of rare secondary coordination in 2 and deprotonated carboxyl functionality of the modified flavin in 3 for silver ion coordination results in discrete, zig-zag and ribbon-like architecture. Crystallographically unique silver ions, anion-pi/lone pair-pi interactions and the argentophilic interactions are some of the unique features observed for silver-flavin complexes. Notably, such extended geometry involving flavin moiety is scarcely reported and these results expand the unexplored coordination horizon of the flavin entities.[a] M.

No abstract

Herein, we report the effect of samarium complexation to the modified flavin entity displaying efficient photocatalytic activity toward sulphoxidation reactions. Single crystal X-ray diffraction studies was performed for the structural characterization of the photocatalyst. Spectroscopic and electrochemical studies was undertaken to better understand the nature of the complex when compared to the un-metalated flavin moiety. While the catalytic efficiency was best observed in 20% water in trifluoroethanol using 1 mol% of the catalyst in presence of Blue LED light under oxygen atmosphere. Insignificant product formation was observed with un-metalated flavin moiety. A wide range of sulphides were used to explore the substrate scope.

No abstract