Heterobimetallic (Fe^II/Pt^II)‑Based Supramolecular Coordination Complexes Using 1,1′-Ferrocene Dicarboxylate: Self-Assembly and Interaction with Carbon Dots

The synthesis and characterization of a new pyrazine-based ditopic organoplatinum­(II) complex having a bite angle of 180° is reported. The facile and efficient syntheses are described of three discrete neutral Fe­(II)/Pt­(II) heterobimetallic SCCs with Pt­(II) acceptor clips of different binding angles, 0, 120, and 180°. These new SCCs were characterized by multinuclear NMR and mass spectrometry. Electrochemical response of these ferrocene containing self-assembled ensembles was studied using cyclic voltammetry. The diplatinum acceptor organometallic clips significantly quench the fluorescence of highly emitting carbon quantum dots (CD), while the self-assembled macrocycles tend to nullify the quenching effect of the organometallic clips. Interestingly, the inefficient quenching of CD fluorescence by these SCCs was found to be directly related to the angular disposition of the binding sites in the Pt­(II) based organometallic clips.