Shape Complementary Coordination Self-Assembly of a Redox-Active Heteroleptic Complex

Abstract

We present here the coordination self-assembly of a new heteroleptic (bpyPd) 4 L 1 L 2 2 coordination complex (1) from one novel pyridinium-functionalized bis-2,4,6-tris(pyridin-3-yl)-1,3,5-triazine (bis-3-TPT, L 1 ) macrocyclic ligand, two separate 3-TPT (L 2 ) ligands, and four cis-blocking bpyPd(NO 3 ) 2 (bpy = 2,2′bipyridine). While homoleptic self-assemblies with either L 1 or L 2 gave dynamic mixtures of products, a single thermodynamic heteroleptic complex was obtained driven by the shape complementarity of building blocks. Moreover, the redox-active nature of the heteroleptic assembly facilitates the highly efficient catalytic aerobic photo-oxidation of aromatic secondary alcohols under mild conditions.

[M8L4]8+-Type Squares Self-Assembled by Dipalladium Corners and Bridging Aromatic Dipyrazole Ligands for Iodine Capture

“…The extensively developed metal-directed self-assembly has evolved as an elegant and efficient strategy for the controllable bottom-up construction of well-defined supramolecular architectures, − which are based on various noncovalent bonds, such as van der Waals, coordination, electrostatic, hydrogen, and halogen bonds. − More recently, functional supramolecular assemblies have played critical roles in catalysis, biological simulations, molecular recognition, host–guest encapsulation, anion sensing, and functional materials because of their structural diversity and excellent physical properties. − So far, all of these supramolecular assembled structures have been exquisitely designed since the 1990s for metal–organic/organometallic square macrocycles (“molecular squares”). ,− Recently, there has been strong interest in the design and function of molecular squares, − and they are widely used in various fields, such as catalysis, luminescence, and anticancer therapy due to the interesting physical and chemical properties of these architectures. − Among multidentate N-donor ligands, pyrazole ligands are often used in the self-assembly of polynuclear pyrazole-bridged ring structures with metal nodes via directional metal–ligand interactions. , In our previous studies, functional square-like metallamacrocycles were prepared via a directed self-assembly approach that exploited metal–ligand and metal–metal bonding interactions. − These macrocyclic metal assemblies have displayed attr...…”

Heteromeric Completive Self-Sorting in Coordination Cage Systems

“…Recently, we and others have developed multiple strategies to control the selective formation of discrete heteroleptic metal–organic structures through integrative self-sorting . Among these, shape-complementary assembly (SCA), − coordination-sphere engineering (CSE), − ligand–ligand interactions, , or guest templation − are the most commonly used. Recently, we have reported an unprecedented Pd 2 ABCD C s - symmetrical assembly where four different bis-monodentate ligands can fuse into a unique discrete cage under thermodynamic control, thus maximizing the structural complexity of such a 4-fold-bridged dinuclear cage.…”

Chiral Induction in a Self‐Assembled Pd4 Coordination Cage with Chiral Guests

“…[24,25] The past two decades have seen the fabrication of numerous symmetric and architecturally precise structures from achiral building units. [26,27] employing various strategies such as coordination sphere engineering, [28][29][30] the use of nonsymmetric ligands, [31,32] and shape-complementary assembly, [33] aimed at enhancing the functionality and complexity of coordination architectures. The synthesis of enantiopure chiral cages has received significant interest due to their potential applications in asymmetric catalysis, [34][35][36] recognition of chiral guest molecules, [37][38][39][40][41] enantioselective sensing, [42] etc.…”