Hydrazone-Linked Covalent Organic Framework Catalyst via Efficient Pd Recovery from Wastewater.

Global consumption and discharge of palladium (Pd) have raised environmental concerns but also present an opportunity for the sustainable recovery and reuse of this precious metal. Adsorption has proven to be an efficient method for the selective recovery of Pd from industrial wastewater. This study investigated a hydrazone-linked covalent organic framework ( COF) as a potential material for the high-affinity adsorption of Pd ions from wastewater, achieving a value of 3.

A water-soluble Pd molecular tweezer for selective encapsulation of isomeric quinones and their recyclable extraction.

Quinones (QN) are one of the main components of diesel exhaust particulates that have significant detrimental effects on human health. Their extraction and purification have been challenging tasks because these atmospheric particulates exist as complex matrices consisting of inorganic and organic compounds. In this report, we introduce a new water soluble PdL molecular architecture (MT) with an unusual tweezer-shaped structure obtained by self-assembly of a newly designed phenothiazine-based tetra-imidazole donor (L) with the acceptor -[(tmeda)Pd(NO)] (M) [ tmeda = ,,','-tetramethylethane-1,2-diamine].

Self-Assembly of an [M L2 ] Intertwined Cube and a Giant [M L1 ] Orthobicupola.

Through coordination-driven self-assembly, aesthetically captivating structures can be formed by tuning the length or flexibility of various components. The self-assembly of an elongated rigid terphenyl-based tetra-pyridyl ligand (L1) with a cis-Pd(II) acceptor produces an [M L1 ] triangular orthobicupola structure (1). When flexibility is introduced into the ligand by the incorporation of a -CH - group between the dipyridylamine and terphenyl rings in the ligand (L2), anunique [M L2 ] water-soluble 'intertwined cubic structure' (2) results.

Water-Soluble PdL Molecular Bowl for Separation of Phenanthrene from a Mixture of Isomeric Aromatic Hydrocarbons.

Phenanthrene is a high-value raw material in chemical industries. Separation of phenanthrene from isomeric anthracene continues to be a big challenge in the industry due to their very similar physical properties. Herein, we report the self-assembly of a water-soluble molecular bowl () from a phenothiazine-based unsymmetrical terapyridyl ligand () and a -blocked 90° Pd(II) acceptor.

Post-Synthesis Conversion of an Unstable Imine Cage to a Stable Cage with Amide Moieties Towards Selective Receptor for Fluoride.

Synthesis of robust covalent macrocycles/cages via multiple amide-bond forming reaction is highly challenging and generally it needs multistep reactions. One-pot reaction of appropriate di-/tri-acyl chloride with a diamine generally results polymers or oligomers instead of discrete architectures. To overcome this limitation, a strategy is reported here using dynamic imine chemistry for facile construction of imine-based macrocycle and cage upon treatment of a diamine with di- and tri-aldehydes respectively, followed by post-synthesis one-step conversion of imine bonds to amides to form the desired robust macrocycle and cage containing multiple amide bonds.

An Adaptable Water-Soluble Molecular Boat for Selective Separation of Phenanthrene from Isomeric Anthracene.

Anthracene crude oil is a common source of phenanthrene for its industrial use. The isolation of phenanthrene from this source is a challenging task due to very similar physical properties to its isomer anthracene. We report here a water-soluble Pd(II) molecular boat () with unusual structural topology that was obtained by assembling a flexible tetrapyridyl donor () with a -Pd(II) acceptor.

Self-Assembly of Octanuclear Pt/Pd Coordination Barrels and Uncommon Structural Isomerization of a Photochromic Guest in Molecular Space.

Two tetragonal molecular barrels and were successfully synthesized by coordination-driven self-assembly of a tetrapyridyl donor () of the thiazolo[5,4-]thiazole backbone with -blocked 90° Pd(II) and Pt(II) acceptors, respectively. The single-crystal structure analysis of revealed the formation of a two-face opened tetragonal Pd molecular barrel architecture. In contrast, the isostructural Pt(II) barrel () is water-soluble.

Self-Assembly of a Pd Macrocycle and Pd Homochiral Tetrahedral Cages Using Poly(tetrazolate) Linkers.

A two-dimensional molecular square () was obtained by the self-assembly of a bis(tetrazole) linker, 4,4'-bis(1-tetrazol-5-yl)-1,1'-biphenyl (H), with a square-planar metal acceptor [ = (tmeda)Pd(NO), where tmeda = ,,','-tetramethylethane-1,2-diamine] in dimethyl sulfoxide (DMSO) followed by crystallization. The uncommon 2,3-binding mode through N atoms of the tetrazole rings in this assembly leads to the formation of an octanuclear molecular square. The molecular square [Pd()(NO)] is unstable in DMSO and slowly converts to a dynamic mixture of a 3D tetrahedral cage [Pd()(NO)] and the macrocycle .

Nucleation of Tiny Silver Nanoparticles by Using a Tetrafacial Organic Molecular Barrel: Potential Use in Visible-Light-Triggered Photocatalysis.

Coordination-driven self-assembly of discrete molecular architectures of diverse shapes and sizes has been well studied in the last three decades. Use of dynamic imine bonds for designing analogous metal-free architectures has become a growing challenge recently. This article reports an organic molecular barrel (OB4 ) as a potential template for nucleation and stabilization of very tiny (<1.