Download or read book Design and Synthesis of Heteroleptic and Heterometallic Metallo-Supramolecular Terpyridine Architectures written by Rajarshi Sarkar and published by . This book was released on 2015 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inspiration from biological assemblies in Nature has produced an extraordinary amount of research in supramolecular chemistry. Various non-covalent interactions have been employed to design and synthesize numerous sophisticated architectures with unique structural and functional properties. Metallo-supramolecular constructs are primarily synthesized in a homoleptic assembly; whereas, a preprogrammed monomer is reacted with a suitable metal ion to produce the desired, highly symmetric architectures. On the other hand, structural variance in the supramolecular materials is instilled mainly by step-wise or dynamic assembly protocols. Owing to the unavailability of suitable building blocks and lack of control over the outcome of the assembly, study of these assembly methods has been limited. Two novel terpyridine-based bimetallic triangles were synthesized via a less explored supramolecular fusion approach. Syntheses of two homometallic cyclic trimer and two metallo-squares were achieved, and they were characterized by NMR and MS techniques. Mixing of triangular and the tetrameric units produced the desired bimetallic triangular complexes in quantitative yield. The multinuclear structures were characterized by 1H, 2D-COSY, 2D-NOESY, ESI- and TWIM-MS data. Tandem MS data provided information on the stability of these triangles. UV-vis and luminiscence data indicated metal-ligand charge transfer. Three bimetallic triangles were constructed by a step-wise directed assembly method. An oligomeric trimer was synthesized from a 60o-directed bisterpyridine ligand and was characterized by NMR and MS techniques. Three heterobimetallic triangular architectures were obtained by reacting the oligomeric trimer with Zn(II), Cd(II), and Fe(II). 1H, 2D-COSY, and 2D-NOESY NMR, ESI- and TWIM-MS data confirmed the proposed structures. Luminescence data showed the emission intensities of the triangles are lower than the linear trimer indicating quenching effect of Zn(II), Cd(II), and Fe(II) centers. Synthesis of a structural mimic of first-generation Sierpiński triangle was achieved via dynamic supramolecular assembly. The two required bis- and tetrakis-terpyridine ligands were synthesized and characterized. The ligands were reacted with Cd(II) in precise 1:1:3 molar ratio to obtain the desired complex in near quantitative yield. 1H, 2D-COSY, and 2D-NOESY NMR, ESI- TWIM-MS, and collision cross-section data confirmed the presence of a Sierpiński triangle as the sole product of the reaction. TEM provided the visualization of the desired architecture, shape, and size of the observed molecules, which fit perfectly the simulated parameters.