R. E. Khoma

Products of interaction between Sulfur(IV) oxide and aqueous solutions of hexamethylendiamine and tert-Butylamine: The crystal structure of hexamethylenediammonium sulfate dihydrate

The possibility of mild SO2 oxidation in sulfur(IV) oxide-alkylamine-water-oxygen systems is demonstrated to yield onium sulfates.

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).

Preparation and some physicochemical properties of benzylammonium sulfates

New method of preparation of multisubstituted benzylammonium cations via interaction in the SO2-L-H2O systems (L is benzylamine, α-phenylethylamine, N,N-dimethylbenzylamine, or dibenzylamine) has been developed. The products have been studied by X-ray diffraction, IR, Raman spectroscopy, and mass spectrometry.

Features of interaction in the sulfur(IV) oxide-hexamethylenetetramine-water system: A first example of identification of the product with a sulfur-carbon bond

Hexamethylenetetramine (HMTA) is a ligand in the synthesis of coordination compounds and also is used as a pharmaceutical antiseptic drug and as hexogen precursor [1]. An attempt is known to use aqueous solutions of HMTA as an absorbent for extracting hydrogen fluoride and sulfur dioxide from the flue gases of aluminum production [2, 3]. In the study on the interaction in the HMTA–H2SO3–H2O system [4] a formation was found of compounds 2HMTA·H2SO3· 6H2O and HMTA·2H2SO3·8H2O, the hexamethylenetetrammonium sulfite and bisulfite, respectively, hydrated forms. On the other hand, in acidic solutions HMTA is prone to hydrolysis to form ammonia and formaldehyde that does not exclude further deeper chemical reactions in the system HMTA–H2SO3–H2O (HMTA–SO2–H2O), as indicates indirectly the formation of Н2NCH2SO3Na in the reaction of sodium hydrosulfite with formaldehyde and ammonia [5]. In this communication we report on the conditions of synthesis and the results of identification of a new compound, H2NCH2SO3H, aminomethanesulfonic acid, first isolated as a reaction product in HMTA–SO2–H2O system: Aminomethanesulfonic acid. A solution of HMTA (5.0 g) in 30 ml of water was loaded to a reactor, cooled, and kept at 0°C for 20 min. Through this mixture gaseous SO2 was bubbled at the rate 50 ml min to рН < 1.0. The amorphous precipitate formed which partly dissolved at further SO2 passage. The solution with precipitate was kept at room temperature in air to complete water evaporation (~10 days). Yield 8.2 g (51.57% by N), white polycrystalline substance. The product was purified by recrystallization from water. Found, %: C 10.92; H 4.33; N 12.80; S 27.93. CH5NO3S. Calculated, %: C 10.81; H 4.54; N 12.60; S 28.86. M 111.1; mp 184°C (decomp.) (184°C [6]). IR spectrum, ν, cm: 3365, 3220, 3160, 3025 (N–H); 2982, 2908 (C–H); 2673, 2620, 2580, 2488, 2400, 1971 (N–H in hydrogen bond); 1230, 1207 (SO2, as), 1060, 1000 (SO2, s), 579 (S–O). The band ν(N–H) in the range of 3365–1970 cm is characteristic of NH3DOI: 10.1134/S1070363211030352

Synthesis, crystal structure, and spectral characteristics of N -(Hydroxyethyl)aminomethanesulfonic acid

A new method of the synthesis of N-(hydroxyethyl)aminomethanesulfonic acid by reaction in SO2-H2NCH2CH2OH-CH2O-H2O system was developed. Compound HO(CH2)2NHCH2SO3H was characterized by XRD, IR and mass spectroscopy.

On interaction of sulfur(IV) oxide with aqueous solutions of ethanolamines

Potentio- and conductometric titration was used to study the interaction in sulfur(IV) oxide-ethanolamines-water systems in comparison with the previously obtained pH-metric data on how the corresponding onium sulfites, hydrosulfites, and pyrosulfites are formed. The ionic and molecular compositions of these solutions were calculated. Correlations between the characteristics of pH-metric titration curves of aqueous solutions of ethanolamines with sulfur(IV) oxide and the relative stability of onium sulfates were revealed.

Complexing of sulfur(IV) oxide with hexamethylenetetramine and hexamethylenediamine in aqueous solutions

Interaction in the sulfur(IV) oxide-hexamethylenetetramine (hexamethylenediamine)-water systems was studied by pH-, redox-, and conductometric titration techniques. The structure and stability of the resulting molecular and ionic complexes were examined in relation to the nature and concentration of the components in solution, as well as to temperature.

Anionic complexes as products of reactions in SO2-carbamide(acetamide)-H2O systems

Evaluation of the contribution of hydrosulfite and pyrosulfite ions in the formation of anionic complexes in the sulfur(IV) oxide-amide-water systems was carried out considering the data of the pH-metric and redox-metric studies. Microconstants of the formation of anionic complexes of carbamide and acetamide with the above-mentioned anions were calculated.

Complex formation of sulfur(IV) oxide with ethylenediamine and its derivatives in water

Data of potentiometric, redox, and conductometric studies of interactions in the sulfur(IV) oxide-ethylenediamine (or its analogs)-water systems, being in fair agreement, have showed the formation of onium sulfites, hydrosulfites, and pyrosulfites. The absorbance capacity of aqueous solutions of ethylenediamines with respect to sulfur dioxide depends on the amino groups amount. Ion and molecular compositions of the studied solutions have been computed, and the relative stability of onium sulfites of ethylenediamine and piperazine has been estimated.

Onium Sulfates and Hydrogen Sulfates: Products of Reactions of Sulfur(IV) Oxide with Aqueous Solutions of Alkylamines and Aniline

The reaction products formed in the SO2–L–H2O–O2 systems (L is n-propylamine, n-butylamine, tert-butylamine, n-heptylamine, n-octylamine, aniline) were isolated and identified as “onium” salts [n-C3H7NH3]2SO4, [n-C4H9NH3]2SO4, [t-C4H9NH3]2SO4, [n-C7H15NH3]3SO4(HSO4), [n-C8H17NH3]3SO4(HSO4), and [C6H5NH3]2SO4. The products were characterized by elemental analysis, IR and Raman spectroscopy, mass spectrometry, and thermogravimetry.