ChemInform Abstract: A New Generation of 6,6′‐Disubstituted 2,2′‐Bipyridines: Towards Novel Oligo(bipyridine) Building Blocks for Potential Applications in Materials Science and Supramolecular Chemistry.

Abstract

The 6,6Ј-disubstituted 2,2Ј-bipyridines and oligo (bipyridines) functionality and reasonable solubility behavior. These molecules permit the synthesis of a wide range of are often used as ligands in supramolecular chemistry; however, their range of application has been limited due to functionalized oligo(bipyridines) with new potential applications in supramolecular chemistry and materials the lack of unsymmetrically functionalized compounds and their poor solubility. We describe herein a new generation of science. As initial examples, we present the synthesis of mono-and bis-functionalized bis-and tris-2,2Ј-biypridines. specially designed unsymmetrical bipyridine building blocks possessing different protecting groups for the hydroxy Introductionother supramolecular systems are rare [9] [10] . This may be explained by the lack of a suitable synthetic route to unsymIn the last two decades, many well-defined supramolecumetrically 6,6Ј-functionalized 2,2Ј-bipyridines or funclar architectures have been achieved by the self-assembly tionalized oligo(bipyridines), and by the relatively low soluof organic components [1] . Possible applications are seen in bility of methyl substituted oligo(bipyridines) [6f] . However, catalysis [2] , electrochemistry [3] , photochemistry [4] , or new such systems should show novel properties due to the helicmaterials [5] . However, only a few systems fulfill the requireity, self-organization and cooperative features of the bipyriments for practical applications such as formation of special dine units. architectures using recognition-directed self-assembly features, availability of the components in usable quantities, and the presence of end groups that can be covalently incor-Results and Discussion porated into networks and assemblies. The most prominent examples for self-organization systems are the 6,6Ј-disubstiThe syntheses of 6,6Ј-disubstituted-2,2Ј-bipyridine building blocks have been a major goal in organic and supramoltuted oligo(2,2Ј-bipyridine) copper(I) or silver(I) complexes with methyloxymethylene linkers between the bipyridine ecular chemistry [11] [12] . Besides efforts towards metal-binding cryptands or spherands (see, for instance, the most units [1a] [1b] [6] due to their ability to spontaneously form well-defined helical architectures, similar to the Watson and prominent example in this field, the "sexipyridine" [13] ), ligand systems for potential antitumor agents [14] or derivaCrick double-helix in nucleic acids [7] . However, only the simple non-functionalized ligands and their complexes are tives for protein labeling [15] , the central interest in the last decade has been focused on the construction of oligo(bipyriknown [6] . A different approach using a stepwise construction starting from different template units was recently de-dine) strands as basic ligands for double helical architectures [1a] [1b] [6] . Non-functionalized oligo(bipyridines) conscribed [8] by Siegel et al. Transformations of such building blocks into other sys-taining two to fiv...

Catalytic Oxidation of 2-Amino-3-Sulfhydryl Propanoic Acid (ASPA) by 2,6- Dicarboxypyridinium Fluorochromate (DCPFC) : A Kinetic and Mechanistic Study

“…2-(Pyridin-2-yl)Pyridine has found its application in various fields of chemistry such as macromolecular, supramolecular, material chemistry, photochemistry, electrochemistry due to their extraordinary coordination properties, as ligands in metal-catalysed reactions [37][38][39][40][41][42][43] . 2-(Pyridin-2-yl)Pyridine framework bears pendent chiral substituents, they have been studied as potential ligands in Metal -Catalysed Asymmetric reactions.…”

“…From the observed kinetic results, the following possible mechanism has been proposed for our kinetic study. In the first step protonated oxidant 21 reacts with 2-(Pyridin-2-yl)Pyridine 39 and forms a complex C1 in the Equilibrium step. After that complex C1 reacts with 2-amino-3-sulfhydryl propanoic acid 34 to form complex C2.…”

Designing new agents for the peloruside binding site

“…A method using silver oxide (Ag2O), which has been shown to substitute a tertiary chloroalkane, 152 again resulted in no chloride substitution, although at least the TMS protecting group was retained with no effect on the starting materials 203 and 204. Lithium iodide has been known to substitute chloride for iodide, [153][154][155] and it was proposed it could be used in a two-step substitution process, swapping chloride for iodide then for hydroxyl. However, upon reaction of 203 and 204 with LiI no change in starting material was observed after three days.…”