Thermophysical property characterization of tris(hydroxymethyl)aminomethane

In this present work, a thermophysical property characterization of aqueous solution of tris(hydroxymethyl)aminomethane (TRIS), a biological buffer, was done. The investigated properties were refractive index (n), density (ρ), and electrolytic conductivity (κ). These properties were measured for temperatures up to 353.15 K (at normal atmospheric condition) and for the entire composition range where TRIS is still soluble in water. The measured properties were reported as functions of temperature and composition. A modified form of the Vogel–Tamman–Fulcher equation which leads to an Arrhenius-type asymptotic exponential function was used to generally correlate the temperature and compositional dependence of the considered properties and satisfactory results were obtained.     

Three-fold polyfluoroalkylated amines and isocyanates based on tris(hydroxymethyl)aminomethane (TRIS)

Three-fold polyfluoroalkylated amines were prepared from tris(hydroxymethyl)aminomethane (TRIS) in five steps including perfluoroalkyl iodide addition to the corresponding allyl derivative, reduction of C-I bond and deprotection of the amino group. They can be easily converted to the corresponding isocyanates.     

Synthesis, crystal structure, vibrational spectra, and thermochemical transformations of tris(hydroxymethyl)aminomethane

A practically promising compound, tris(hydroxymethyl)aminomethane sulfate ((TRISH)₂SO₄, C₈H₂₄N₂O₁₀S) was synthesized and studied by a set of experimental methods (elemental analysis, IR and Raman spectroscopy, mass spectrometry, thermogravimetry).     

High-performance liquid chromatographic method for the determination of tris(hydroxymethyl)aminomethane (tromethamine) in human plasma.

Determination of tris(hydroxymethyl)aminomethane (tromethamine) in human plasma involved derivatization of the amino and hydroxyl groups with a ultraviolet-absorbing chromophore followed by extraction into an organic phase. Reversed-phase high-performance liquid chromatography with gradient elution was used for the separation of the analyte from the internal standard (2,3-butanediol). The assay was linear in the range 1.0-1000.0 micrograms/ml of plasma and the coefficient of variation varied between 9.6 and 16.3% whereas the accuracy varied between 90 and 108%. The limit of detection for the assay was 0.282 micrograms/ml. Stability of tris(hydroxymethyl)aminomethane in human plasma frozen at -20 degrees C was studied over a period of three month and the data indicated no significant change.     

Acid association quotients of tris(hydroxymethyl)aminomethane in aqueous NaCl media to 200°C

The molal acid association quotients of tris(hydroxymethyl)aminomethane (Tris, also abbreviated as THAM) were determined potentiometrically in a concentration cell fitted with hydrogen electrodes. The emf was recorded for equimolal Tris/Tris-HCl buffer solutions from 5 to 200°C at approximately 25° intervals, and at ionic strengths of 0.0759, 0.2012, 0.7232, 1.9996, 3.5077, and 4.9599. The molal association quotients, as well as those selected from the literature and calorimetrically-determined enthalpies of reaction, were simply described by a six parameter equation which yielded the following thermodynamic quantities at infinite dilution and 25°C: logK=8.071±0.009, H° = -47.53 ± 0.13 kJ-mol^-1, S° = -4.9 ± 0.5 J-K^-1-mol^-1, and C _p ^° = 67 ± 13 J-K^-1-mol^-1. The fitting equation for this isocoulombic reaction incorporates a four term expression for log K and a linear isothermal dependence on ionic strength.     

Reactivite du tris(hydroxymethyl)aminomethane avec des nitro-aldehydes aromatiques. Synthese de nouveaux composes antimicrobiens.

Heterogeneous reaction of TRIS 1 with nitro-aldehydes leads to oxazolidines in good yield. New products are obtained as monocyclic or bicyclic compounds, and are of potential medicinal value.     

Tris(hydroxymethyl)aminomethane—a primary standard?

Commercially available "primary standard" grade tris(hydroxymethyl)aminomethane (THAM) may not always be of the requisite quality. Crystals of THAM can contain large amounts of occluded mother liquor. Material which has been ground, dried in vacuum, further ground, sifted through a 100-mesh sieve, and finally dried in vacuum, will approach 100% in purity.     

Lamellar molybdenum oxide as a molecular sieve towards nitrogen containing molecules: intercalation compounds with pyridazine, acrylamid and tris(hydroxymethyl)aminomethane

The synthesis and characterization (by CHN elemental analysis, FTIR spectroscopy, XRD diffractometry, thermogravimetry and SEM microscopy) of MoO₃ intercalation compounds with pyridazine (pdz), acrylamid (ald) and tris(hydroxymethyl)aminomethane (tham) is reported. Such investigation was performed taking into account the possible uses of molybdenum trioxide as a molecular sieve towards nitrogen containing compounds. It is verified that the affinity of MoO₃ towards the investigated species follows the sequence: ald ? tham > pdz.     

Aqueous complexation studies of lead(II) and cadmium(II) with 1,3-bis(tris(hydroxymethyl)methylamino)propane pH buffer

Hydrogen buffers are important in biological studies, as a steady hydrogen concentration is of great importance in most scientific studies. One of these buffers is 1,3-bis(tris(hydroxymethyl)methylamino)propane (BTP), which, considering its structure, has complexing capabilities, as previously shown for other metals. In order to know the stability constants for Cd(II) or Pb(II) with BTP, glass electrode potentiometry and direct current polarography studies were carried out. Our results show that both metals form metal complexes, with Pb(II) forming stronger complexes with BTP as evidenced by its higher stability constants. In the Pb-BTP system, five species were described; PbHL, PbL, PbL₂, PbL₂(OH), and PbL₂(OH)₂, and their stability constants were determined to be 11.4 ± 0.3, 4.7 ± 0.3, 8.8 ± 0.2, 14.4 ± 0.3, and 18.4 ± 0.3, respectively. For the Cd-BTP system, four complexes were detected; CdHL, CdL, CdL(OH), and CdL(OH)₂, and their stability constants were also determined as 10.9 ± 0.4, 4.10 ± 0.07, 8.2 ± 0.2, and 10.9 ± 0.2, respectively. These complexes decrease considerably the amount of free metal in solution within the buffering pH range. This fact should be considered when planning experiments were BTP and Pb(II) and/or Cd(II) ions are present.     

Dissociation constant of protonated tris(hydroxymethyl)aminomethane in N-methylpropionamide and related thermodynamic quantities from 10 to 55°C

The dissociation constant of protonated tris(hydroxymethyl)aminomethane (tris·H⁺) in the solvent N-methylpropionamide (NMP) has been determined at intervals of 5°C from 10 to 55°C by measurement of the emf of cells without liquid junction using hydrogen and silver-silver chloride electrodes. At 25°C, pK _a was found to be 8.831, as compared with 8.075 in water. The standard changes in Gibbs energy, enthalpy, and entropy for the dissociation process have been evaluated from the dissociation constant and its change with temperature. By comparison with similar data for the dissociation of tris·H⁺ in water, thermodynamic functions for the transfer from water to NMP have been derived. The dissociation process is isoelectric, and the solvent dielectric constant is high (=176 at 25°C). Consequently, electrostatic charging effects are expected to be minimal, and the change in dissociation constant depends primarily on solute-solvent interactions. The results, combined with transfer energies for HCl, tris, and tris·HCl from emf and solubility measurements, demonstrate that the decreased acidic strength of tri·H⁺ in NMP is attributable in large part to the fact that NMP is less effective than water in stabilizing tris and its salts.     

Syntheses and rearrangements of tris(hydroxymethyl)phosphine and tetrakis(hydroxymethyl)phosphonium salts

Abstract

Tetrakis(hydroxymethyl)phosphonium (HOCH₂)₄P⁺ salts, particularly the chloride (THPC) and sulfate (THPS), are among the most accessible organophosphorus compounds that can be made quantitatively from PH₃ and formaldehyde in aqueous media under ambient conditions. These phosphonium salts are air-stable, and are widely used as reactants in organic syntheses, as well as in textile or oil industries. Synthesis of tris(hydroxymethyl)phosphine (THP), an active component of the salts, is more complicated because direct synthesis from PH₃ and CH₂O requires either pressure and high temperature, at which THP rearranges into bis(hydroxymethyl)methylphosphine oxide, CH₃P(O)(CH₂OH)₂, or a metal catalyst that is usually difficult or impossible to recover. Syntheses of THP based on neutralization of the salts are more convenient but require pH control and additional steps to separate THP from CH₂O. This review summarizes literature data on syntheses and purification of the salts and THP, and side reactions such as thermal rearrangement and oxidation.     

Catalytic etherification of N-protected tris(hydroxymethyl)aminomethane for the synthesis of ligands with C3 symmetry

The synthesis of two nonadentate ligands based on a N,N-dibenzylated-tris(hydroxy)methylaminomethane framework is described. The key step consists in tris-etherification of the precursor with elaborated pyridine and bipyridine derivatives and this was greatly improved by the introduction of catalytic amounts of tetrabutylammoniumiodide to the reaction mixture in DMF at room temperature. Analysis of the alkylation rates and an X-ray crystal structure of a bis-alkylated intermediate strongly support the presence of a tight intramolecular hydrogen bond, preventing a fast third alkylation step. The two acidic ligands were successfully prepared by combining a sequence of carboalkoxylation and hydrolysis of the corresponding esters. Both ligands react with europium and terbium chloride salts to generate water luminescent mononuclear complexes.     

Double function of tris(hydroxymethyl)aminomethane (THAM) for the preparation of colloidal silica nanospheres and the conversion to ordered mesoporous carbon

Tris(hydroxymethyl)aminomethane (THAM) has been found to be an excellent catalyst for the preparation of colloidal silica nanospheres around 10 to 20 nm in size, and THAM on the surfaces of nanospheres is an efficient carbon source for the synthesis of highly ordered mesoporous carbon with controlled pore size by using closely packed nanospheres as a porogen.     

Effect of tris(hydroxymethyl) aminomethane on the phase behavior of poly(ethylene imine)/cinnamic acid conjugate and the release property of cubic phase containing the conjugate

The upper critical solution temperature (UCST) of poly(ethylene imine)/cinnamic acid (PEI/CA) conjugate decreased as the tris(hydroxymethyl) aminomethane (THMAM) concentration increased. On the optical micrographs of PEI/CA mixture solutions at 25°C, the microspheres were found when the THMAM concentration was 0?mM and 100?mM, but hardly found at 200?mM. Monoolein (MO) cubic phase containing PEI, CA, and THMAM exhibited a bilayer structure on the TEM micrograph. The release degree of methylene blue loaded in the cubic phase was not strongly dependent on THMAM concentration at 25°C and 37°C, but strongly dependent on the concentration at 50°C.     

Synthesis and study of organic nitrates of the heterofunctional series 3. Synthesis and structure of tris(hydroxymethyl)aminomethane dinitrate benzoate hydronitrate

Tris(hydroxymethyl)aminomethane dinitrate benzoate hydronitrate, the first representative of mixed nitric and carboxylic esters of aminopolyatomic alcohols, was obtained by the reaction of a mixture of concentrated HNO₃ and Ac₂O with 4,4-bis(hydroxymethyl)-2-phenyl-2-oxazoline. X-ray structural analysis demonstrated that the title compound exists in the crystal as two independent molecules. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 505–509, March, 1999.     

Extraction of europium from nitrate solutions in the presence of tris(hydroxymethyl)aminomethane and characterization of the products of pyrolysis of extracts

The extraction of europium by neat benzene and benzene solutions of tributyl phosphate (TBP) and benzoic acid (BA) was studied in the presence of tris(hydroxymethyl)aminomethane (THMAM). Based on europium distribution in these extraction systems in combination with the IR and luminescence spectra of extracts, we infer that well-extractable europium complexes with THMAM are formed. We demonstrate that introduction of THMAM into aqueous nitrate solutions considerably enhance europium extraction. The compositions are determined and some magnetic properties of pyrolysis products of extracts are studied.     

Developments in the chemistry of tris(hydroxymethyl)phosphine

Tris(hydroxymethyl)phosphine, P(CH₂OH)₃, a water-soluble compound, has been known for about 50 years but development of its coordination chemistry has been slow and relatively recent. During some collaborative studies with a pulp and paper research institute on testing water-soluble catalysts for hydrogenation of lignin in pulp and the unsaturated functionalities in lignin model compounds, with the aim of bleaching pulps, we discovered new, in situ, Ru-P(CH₂OH)₃ hydrogenation catalysts. Interest in the coordination chemistry of this phosphine thus ensued, and this review covers this topic as well as the coordination chemistry of a diphosphine analogue, bis[bis(hydroxymethyl)phosphino]ethane, (HOCH₂)₂P(CH₂)₂P(CH₂OH)₂. The applications of the water-soluble metal complexes of these two phosphines in the areas of catalysis and medicinal drugs are also described. These phosphines, in the absence of metals, were found serendipitously to be effective bleaching agents for pulps (and also brightness stabilizing agents), and some relevant organo-phosphorus chemistry from our group is also briefly presented, particularly because of its possible significance in hydroformylation and hydrogenation processes catalyzed by metal–phosphine complexes.     

Reaction of tris(hydroxymethyl)phosphine and cinnamaldehyde in methanol

Reaction of tris(hydroxymethyl)phosphine with excess cinnamaldehyde in CH₃OH or CD₃OD, followed using NMR, proceeds via several phosphorus-containing intermediates, multiple transformations of organic parts, and with the solvent H/D isotope effect on products. In both solvents, one CH₂OH group of tris(hydroxymethyl)phosphine is readily replaced by the cinnamaldehyde moiety to give the primary product, a 1,3-oxaphosphorinane derivative. Slower replacement of the second CH₂OH group leads to a mixture of aliphatic and heterocyclic phosphine intermediates in a ratio of ~4:1 in CH₃OH and ~1:1 in CD₃OD; both intermediates contain alcohol and aldehyde groups and convert rapidly into intra- and intermolecular hemiacetals. The hemiacetals of the aliphatic phosphine rearrange further into an unsymmetrical trialkylphosphine oxide, whereas the hemiacetals of the heterocyclic phosphine react with the third mole of cinnamaldehyde to replace the third CH₂OH group of tris(hydroxymethyl)phosphine. All intermediates and products are formed as mixtures of stereoisomers.