Tris 3-aminopropyl Amine Research Articles

Selective Liquid-Liquid Extraction of Thorium(IV) from Rare-Earth Element Mixtures.

One of the major challenges in processing rare-earth element (REE) materials arises from the large amounts of radioactive thorium (Th) that are often found within REE minerals, encouraging enhanced metal separation procedures. We report here a study aimed at developing improved systems for REE processing with the goal of efficient extraction of Th(IV) from acidic solution. A tripodal ligand, TRPN-CMPO-Ph, was prepared that utilizes carbamoylmethylphosphine oxide (CMPO) chelators tethered to a tris(3-aminopropyl)amine (TRPN) capping scaffold. The ligand and its metal complexes were characterized by using elemental analysis, NMR, Fourier transform infrared spectroscopy, mass spectrometry, and luminescence spectroscopy. Using a liquid-liquid metal extraction protocol, TRPN-CMPO-Ph selectively extracts Th(IV) at an efficiency of 79% from a mixture of Th(IV), UO22+, and all rare-earth metal cations (except promethium) dissolved in nitric acid into an organic solvent. Th(IV) extraction selectivity is maintained upon extraction from a mixture that approximates a typical monazite leach solution containing several relevant lanthanide ions, including two ions at higher concentration relative to Th(IV). Comparative studies with a tris(2-aminoethyl)amine (TREN)-capped derivative are presented and support the need for a larger TRPN capping scaffold in achieving Th(IV) extraction selectivity.

Macrocyclic Compounds Comprising Tris(3-Aminopropyl)Amine Units and Fluorophore Moieties: Synthesis and Spectroscopic Studies in the Presence of Metal Salts

The synthesis of a variety of polyazamacrocyclic compounds comprising structural units of tris(3-aminopropyl)amine (TRPN) and oxadiamines, decorated with one or two fluorophore groups (dansyl or quinoline) at different nitrogen atoms, was carried out using Pd(0)-catalyzed amination. The dependence of the yields of the macrocycles on the synthetic path was observed. The spectrophotometric and fluorescent properties of the target compounds were studied, and their coordination with metal cations using UV–vis, fluorescence spectra as well as NMR titration was investigated. The stoichiometry and binding constants of several complexes with Cu(II), Zn(II), Cd(II), Pb(II) and Hg(II) were established. Three of the six studied macrocycles can be judged as prospective detectors of Zn(II) cations due to the substantial enhancement of fluorescence.

C3V symmetric tripodal molecular pocket for linear anions: Selective colorimetric detection of azide through N4-Cu-π···hole interactions.

Tris(3-amino propyl)amine (TRPN) based C3v symmetric tripodal molecular pocket, L has been prepared and mono copper complex of L, (1) having Cu-N4-π··· hole as recognizing elements, becoming a potential and selective colorimetric chemo sensor for perfect linear recognition of N3-, generate a Cu-NNN- π··· hole unit inside the tripodal pocket. Systematic spectrometric and naked-eye colorimetric studies reveal that, this chemo sensor is also colorimetrically recognizing the cyanide ion by its cavity via Cu-N4-π···hole interactions; nevertheless, when azide anion is entering as a guest into the molecular pocket of 1 which is already hosted cyanide anion, then host displaces cyanide ion, subsequently azide is getting inside the cavity. The strength of the copper complex, 1 towards azide and cyanide are found to be 2.36×103M-1, and 1.87×103 M-1 respectively in 7:3 acetonitrile:water solvent medium. Further, the ability of cyanide displacement by azide in complex 1 is found to be 2.53×103 M-1. To the best of our knowledge, this is the first example of naked-eye detection of azide via cyanide displacement assay by a tripodal receptor.

Layer-by-Layer Assembly of High-Performance Electroactive Composites Using a Multiple Charged Small Molecule.

Layer-by-layer (LbL) assembly is a versatile tool for fabricating multilayers with tailorable nanostructures. LbL, however, generally relies on polyelectrolytes, which are mostly insulating and induce large interlayer distances. We demonstrate a method in which we replace polyelectrolytes with the smallest unit capable of LbL self-assembly: a molecule with multiple positive charges, tris(3-aminopropyl)amine (TAPA), to fabricate LbL films with negatively charged single-walled carbon nanotubes (CNTs). TAPA introduces less defects during the LbL build-up and results in more efficient assembly of films with denser micromorphology. Twenty bilayers of TAPA/CNT showed a low sheet resistance of 11 kΩ, a high transparency of 91% at 500 nm, and a high electronic conductivity of 1100 S/m on planar substrates. We also fabricated LbL films on porous foams with a conductivity of 69 mS/m and used them as electrodes for supercapacitors with a high specific capacitance of 43 F/g at a discharging current density of 1 A/g.

Vapor-phase crosslinked mixed matrix membranes with UiO-66-NH2 for organic solvent nanofiltration

In this work, a series of mixed matrix membranes (MMMs) containing nano-size amine-functionalized UiO-66 particles were vapor-phase crosslinked by tris (3-aminopropyl) amine (TAPA) and investigated for organic solvent nanofiltration (OSN) applications. A thin dense layer was successfully formed on top of MMMs which improved solute selectivity in isopropanol (IPA). By manipulating (1) the size and loading of UiO-66-NH2 nanoparticles in dope solutions, and (2) the temperature and duration of the TAPA vapor crosslinking reaction, we have fabricated a membrane with a 99.2% rejection towards negatively charged Rose Bengal (RB, Mw= 1017 gmol−1) in IPA and a pure IPA flux of 11.5 Lm−2 h−1 at 10 bar. Interestingly, the optimal composite membrane developed in this study shows impressive rejections towards positively charged dyes possibly because of electrostatic repulsion (e.g., Donnan exclusion). In addition, the optimized TAPA vapor-phase crosslinked MMMs display stable performance in various organic solvents and the 14-day rejection test. To our best knowledge, this is the first report on organic solvent nanofiltration MMMs made from the vapor-phase crosslinking modification. This modification method may have great potential to develop next-generation OSN membranes for the separation of organic solvents and solutes in pharmaceutical and food industries.

A Comparison of the Selectivity of Extraction of [PtCl6](2-) by Mono-, Bi-, and Tripodal Receptors That Address Its Outer Coordination Sphere.

Extraction and binding studies of [PtCl6](2-) are reported for 24 mono-, bi-, and tripodal extractants containing tris(2-aminoethyl)amine (TREN) or tris(3-aminopropyl)amine (TRPN) scaffolds. These reagents are designed to recognize the outer coordination sphere of [PtCl6](2-) and to show selectivity over chloride anion under acidic conditions. Extraction from 0.6 M HCl involves protonation of the N-center in tertiary amines containing one, two, or three urea, amide, or sulfonamide hydrogen-bond donors to set up the following equilibrium: 2L(org) + 2H(+) + [PtCl6](2-) ⇌ [(LH)2PtCl6](org). All reagents show higher Pt loading than trioctylamine, which was used as a positive control to represent commercial trialkylamine reagents. The loading of [PtCl6](2-) depends on the number of pendant amides in the extractant and follows the order tripodal > bipodal > monopodal, with urea-containing extractants outperforming amide and sulfonamide analogues. A different series of reagents in which one, two, or three of the alkyl groups in tris-2-ethylhexylamine are replaced by 3-N'-hexylpropanamide groups all show a comparably high affinity for [PtCl6](2-) and high selectivity over chloride anion in extractions from aqueous acidic solutions. (1)H NMR titration of three extractants [LH·Cl] with [(Oct4N)2PtCl6] in CDCl3 provides evidence for high selectivity for [PtCl6](2-) over chloride for tri- and bipodal extractants, which show higher binding constants than a monopodal analogue.

Self-Enhanced Electrochemiluminescence Nanorods of Tris(bipyridine) Ruthenium(II) Derivative and Its Sensing Application for Detection of N-Acetyl-β-d-glucosaminidase.

A self-enhanced electrochemiluminescence (ECL) reagent, synthesized by covalently linking bis(2,2'-bipyridyl)(4'-methyl-[2,2']bipyridinyl-4-carboxylicacid) ruthenium(II) (Ru(bpy)2(mcbpy)(2+)) with tris(3-aminopropyl)amine (TAPA), has been chosen as precursor to prepare nanorods ([Ru(bpy)2(mcbpy)(2+)-TAPA]NRs) with high luminous efficiency via a solvent-evaporation-induced self-assembly procedure. Due to the shorter electron-transfer path and less energy loss, the intramolecular reaction between the luminescent Ru(bpy)2(mcbpy)(2+) and coreactive tertiary amine group in TAPA has shown improved luminous efficiency compared with the common intermolecular ECL reactions. Moreover, using the electrochemiluminescent Ru(II)-based complex as precursor to directly prepare a nanostructure with high electro-active surface area is a more effective and convenient method for enhancing the immobilized amount of Ru(II)-based complex in the construction of biosensors compared with the traditional immobilized methods. Meanwhile, the obtained nanorods could be further functionalized easily, owing to their positive electrical property and the amino group on the surface. Here, Pt nanoparticles functionalized [Ru(bpy)2(mcbpy)(2+)-TAPA]NRs are used to load the detection antibody (Ab2). In addition, the Au/Pd dendrimers (DRs) with hierarchically branched structures are synthesized to immobilize capture antibody (Ab1) with increased amount. Based on sandwiched immunoreactions, a simple and sensitive "signal-on" immunosensor is constructed for the detection of N-acetyl-β-d-glucosaminidase (NAG), a biomarker of diabetic nephropathy, with excellent linearity in concentrations from 1 ng mL(-1) to 0.5 pg mL(-1) and a detection limit of 0.17 pg mL(-1).