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The platinum(II) complexes [Pt(N-N)X 2 ] (X = Cl, Br, and I; (N-N) = 1,2-ethanediamine (en) and 1,3-propanediamine (tn)) have been synthesised; their reactions with DMSO in DMSO to substitute halogenide were followed using changing integrals of NMR-spectroscopic signals. The rate constant for [PtenCl 2 ] was found to be 1.0*10 −4  s −1 at 300 K and from kinetic runs at different temperatures the energy of activation was estimated as 82 kJ*mol −1 in this case. The rate constant depends on the size of halogenide and was found to be forty times larger for [PtenI 2 ] than for its dichloro-analogue. In the tn-series reactions were a little faster than in the en-series. For all six [Pt(N-N)X 2 ] complexes the solvolysis stopped at the coordination of one DMSO and the six new [Pt(N-N)DMSOX]X were isolated and characterised. Further the [PtenDMSOCl] + was isolated as its nitrate and perchlorate. DMSO exchange reactions (in DMSO) of [PtenDMSOX] + were found to be slightly slower than the solvolysis reactions, iodide again giving rise to the most labile system. Ion pair formation in DMSO was found to be modest to almost negligible with a formation constant of 30 M −1 in the case of [PtenDMSOCl]Cl as the largest. [ABSTRACT FROM AUTHOR]

Reaction between substituted thiazolylamine or oxazolylamine, triethyl orthoformate and sodium azide in the presence of tributylmethylammonium chloride in DMSO furnishes 1-substituted 1H-1,2,3,4-tetrazole in high yield. [ABSTRACT FROM AUTHOR]

The first simple, metal free, and efficient protocol has been established for the methylthiolation of structurally diverse 4-bromomethyl-2H-chromen-2-ones using dimethyl sulfoxide (DMSO) as methylthiolation source at higher temperature. The experimental method is highly economical and provides excellent yields of highly pure products which do not require further purification. All novel 4-[(methylthio)methyl]-2H-chromen-2-ones were characterized by1H,13C NMR, and single-crystal X-ray analysis. [ABSTRACT FROM AUTHOR]

A new modified van Leusen strategy has been developed for the synthesis of biologically significant 5-substituted oxazoles by the reaction of (het)aryl methyl alcohols or benzyl bromides as precursors with tosylmethylisocyanide (TosMIC) under basic conditions. This method is efficient, takes place under mild reaction conditions, and is tolerant of various functional groups with high yield. [ABSTRACT FROM AUTHOR]

(NHC)Rh(CO) 2 Cl complexes interconvert reversibly in the presence of DMSO to the corresponding (NHC)Rh(DMSO)(CO)Cl complexes. The exchange of coordinated for free DMSO was investigated by NMR spectroscopy. The X-ray structure of compound 6a revealed that the CO ligand trans to the NHC had been replaced by S-bound DMSO. In addition, the reactivity of (NHC)Rh(CO) 2 Cl complexes towards other types of ligands like amines, NHCs and phosphines was investigated. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Direct formation of β-keto sulfones. • Dimethyl sulfoxide (DMSO) serves as green oxidant. • Available starting materials, good functional group tolerance. Abstract The oxidative sulfonylation of ketones with sodium sulfinates as the sulfone source and DMSO as the oxidant is reported. A series of β-keto sulfones were obtained in good to excellent yields. The advantages of this efficient protocol include the low cost of DMSO and HBr, and a broad scope. [ABSTRACT FROM AUTHOR]

An efficient and facile α-hydroxylation of ketones catalyzed by CuBr 2 or HBr in DMSO is developed, providing secondary/tertiary α-hydroxy carbonyl compounds in moderate to good yields (up to 87%). A series of control experiments suggested that water and DMSO may work cooperatively in the hydrolysis step. [ABSTRACT FROM AUTHOR]

A facile access to α-ketoamides employing an efficient I 2 -DMSO promoted oxidative coupling reaction conditions between commercially available arylmethylketones and amines under metal free condition is presented. Mechanistic studies revealed C 1 -oxygen atom of α-ketoamides is derived from DMSO. [ABSTRACT FROM AUTHOR]

An I2-DMSO promoted novel and efficient method is described for the synthesis of isatins from 2-aminoaryl methyl ketone. A series of alkyl or aryl isatin derivatives were successfully synthesized under the optimized reaction conditions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Isothermal VLE phase boundaries were measured via synthetic method. [•] The investigated systems are CO2 +DMSO+ethanol and CO2 +chloroform+methanol. [•] The critical points of each pseudo-binary system were estimated from experimental results. [•] The Peng–Robinson equation with van der Waals one-fluid mixing rules were used in this study. [ABSTRACT FROM AUTHOR]

Highlights: [•] High yield of 5-ethoxymethylfurfural was obtained from fructose in one-pot. [•] 5-Ethoxymethylfurfural can be efficiently extracted from the reaction solution. [•] The content of DMSO and its effect on the reaction were studied. [•] H3PW12O40 was found to be an effective catalyst for the present reaction. [Copyright &y& Elsevier]

Dimerization and formylation of p-alkyl-substituted phenols have been successfully achieved in one pot, using 2,4-dichloro-6-methoxy[1,3,5]triazine (DCMT)-activated dimethylsulfoxide. Similarly, the d5-labeled products have been prepared in high selectivity. To the best of our knowledge, the products are of new skeletons, which have not been reported to date. A plausible mechanism is proposed based on the experiments. [ABSTRACT FROM PUBLISHER]

Abstract: Two-electron reduction of PdX2(NHC)2 with Groups 1, 2 metals (K, Mg) is a convenient route to Pd(NHC)2 complexes including Pd(IMe)2 (2a), isolated and crystallographically characterized as the least sterically encumbered d10 M(0)L2 species to date. 2a exhibits a regular linear geometry and modest Lewis acidity to coordinating solvents and additional IMe. In contrast to its analogs with bulkier NHC= I tBu and IPr, 2a undergoes cleanly net oxidative addition of the Me–S(O)Me bond of DMSO, forming trans-PdMe(S(O)Me)IMe2 (3) at RT. DFT calculations suggest this reaction to proceed by substitution of IMe by κS-DMSO followed by concerted C–S oxidative addition to Pd with a single IMe, with a preference of ca. 10kcal/mol in the effective ΔGs ‡ over the direct pathway. Calculations also identify two facile intramolecular pathways for racemization of Pd(II) methylsulfinyl complexes at sulfur. [Copyright &y& Elsevier]

Dimethyl sulfoxide converts 4-acetoxycoumarin (1) exclusively to 2-(2-hydroxybenzoyl)-2-[(methylthio)methyl]-2,3-dihydro-4 H-furo[3,2-c]chromen-4-one (3) at 180°C under a nitrogen atmosphere, but in the absence of nitrogen, the products obtained are dicoumarol and its dehydrative cyclization products 7 H-bis[1]benzopyrano[4,3-b: 3',4'-c]pyran-6,8-dione (9) and (3). Under similar conditions, 4-benzoyloxycoumarin (1a) affords benzoic acid, 4-hydroxy-3-({2-[(methylthio)methyl]-3-oxo-2,3-dihydro-1-benzofuran-2-yl}methyl)-2H-chromen-2-one (7), and 3-(2-hydroxybenzoyl)-3,4-dihydro-2H,5H-pyrano[2,3-b] chromen-5-one (8). [ABSTRACT FROM AUTHOR]

Abstract: Densities (ρ, 10−3kg m−3), viscosities (η, 10−1kg m−1 s−1) and surface tension (γ, mN m−1) of 1 to 5 mg%/100 mL praseodymium (Pr) Sal2en (N,N''-dihydroxybenzalethylene) complex at an interval of 1 mg%/100 mL with dimethylsulphoxide (DMSO) were studied at 293.15, 298.15 and 303.15 K temperatures. The ρ data are used for apparent molal volume (Vϕ 10−6m3 mol−1), η and γ calculations. The η values are fitted in the extended Jones–Dole equation (η r −1)/ c vs c (c = concentration) for coefficient B (kg L−1) and slope D (kg L−1)2. The γ values are regressed against c for limiting surface tension (γ 0) at infinite dilution (c →0). Similarly, limiting apparent molal volume (Vϕ 0) or partial molal volumes (V̄2 0) were derived from the Vϕ values for Pr complex interactions with DMSO. Partial molal volume (V̄2 0) of DMSO was calculated from its ρ value. Free energies of activation of viscous flow (Δμ 1 0⁎/kJ mol−1) per mol of DMSO was calculated from its V̄2 0 and η 0 data and the Δμ 2 0⁎ of Pr complex, from its B, V̄2 0 and V̄2 0 values. The free energy of activation for dropwise flow (Δμ 2 0⁎surf) were evaluated from γ 0 values. The Δμ 1 0⁎and Δμ 2 0⁎ activation energies assess the structure making and breaking action of the Pr complex on DMSO. The coefficient B depicts a critical size of the Pr complex–DMSO interaction based on solute–solvent interaction theories and hence its values have been associated with transition state theory and explain positive transitions of interacting molecules. The ρ values at 293.15 and 303.15 K are higher than those of the DMSO with lower values at 298.15 K. The η values of DMSO are higher than those of the Pr complex. The Δμ 1 0⁎ >0>Δμ 2 0⁎ model of Δμ 2 0⁎ defines the Pr complex–DMSO as nonideal systems with a huge shift in Δμ 2 0⁎ values from DMSO to Pr complex. [Copyright &y& Elsevier]

Dimethyl sulphoxide (DMSO) is an important polar aprotic solvent, less toxic than other members of this class. Because of its excellent solvating power, DMSO is frequently used as solvent for chemical reactions involving salts, especially Finkelstein reactions and other nucleophilic substitutions. Furthermore, DMSO is used as auxiliary substance in toxicity tests on aquatic organisms, usually at concentrations of 0.2 and 0.5 ml·l-1. The aim of the present study was to evaluate the effect of DMSO on early development, growth and mortality of early life stages in common carp. Tests were performed from fertilized egg to the end of the larval period with continuous exposure to DMSO at concentrations of 0.2, 0.5, 1.0 and 5.0 ml·l-1. Mortality of embryos and larvae, intensity of development and growth, weight and occurrence of abnormalities were analyzed. DMSO exposure at all the tested concentrations did not result in any lethal effects or abnormalities compared to the control over the entire test period (29 days). Growth indicators were similar in DMSO treated (at concentrations of 0.2, 0.5 and 1.0 ml·l-1) and control groups. However, mean body weight (35 ± 9 mg) of larvae exposed to the highest DMSO concentration (5 ml·l-1) tested was significantly lower compared to the control (45 ± 14 mg). [ABSTRACT FROM AUTHOR]

Abstract: Typically 2,2-diethylmalonate (dem) acts as a chelating ligand and binds to the metal in a η2 (dem-O, O′) mode. However, when cis,fac-[RuCl2(TMSO-S)4] is treated with K2(dem), it prefers to bind in an unusual bridging mode (μ-dem-O, O′) with the ruthenium (II) cation containing coordinated water, forming a strong hydrogen bond with the non-coordinated oxygen atoms of the 2,2-diethylmalonate ligand. The reaction products of cis,fac-[RuCl2(TMSO-S)4] (1) and cis,fac-[RuCl2(DMSO-S)3(DMSO-O)] (2) with dem are the dinuclear species with two bridging dem units, fac-[Ru(TMSO-S)3(H2O)(μ2-dem-O, O′)]2 (3) and fac-[Ru(DMSO-S)3(H2O)(μ2-dem-O, O′)]2 (4), respectively. The complex 3 was characterized by X-ray crystallography in which water ligands occupy anti positions with respect to each other. The NMR and X-ray study support each other with respect to dinuclear structure of 3 and 4, indicating that the dinuclear structure observed in the solid state is preserved in solution as well. The mononuclear anionic complex with chelating dem unit, K{fac-[RuCl(η2-dem-O, O′)(TMSO-S)3} (5), was also isolated from the reaction of 1 and K2(dem) demonstrating that 5 is an intermediate in the formation of 3. [Copyright &y& Elsevier]

Abstract: The catalytic liquid-phase Beckmann rearrangement of cyclohexanone oxime to ε-caprolactam over solid sulfonic acid resin in dimethyl sulfoxide (DMSO) has been successfully performed. The influences of solvent, catalyst, reaction temperature and reaction time on the rearrangement of cyclohexanone oxime in the liquid-phase were examined. The results indicate that conversion of oxime can reach 100% with 97.9% of selectivity to ε-caprolactam under optimal reaction conditions. This catalytic system involved is environmentally harmless, easily separate, and the catalyst can be conveniently recovered for recycled use. [Copyright &y& Elsevier]

Abstract: Conventional polymerized polyaniline (PANI) dissolved in dimethyl sulphoxide (DMSO) was used as ‘seed’ to induce the polymerization of aniline and hence prepare PANI nanofibers. The different preparation conditions including acid concentration, reaction time, aniline concentration, PANI/DMSO amount, PANI/DMSO concentration, acid and organic solvent kinds were investigated to discuss the influence of these conditions on the morphology and conductivity of the resulting samples. FT-IR spectra were measured to give further proof for the different effect on the conductivity. The scanning electro microscope images of PANI product extracted from the reaction solution at different time were collected and a comparison between this ‘seeding’ polymerization, conventional and rapidly mixing polymerization was also made to make clear the advantage of this approach and the mechanism of the formation of PANI nanofibers. [Copyright &y& Elsevier]

Oxidative cyclocondensation of 2-aroylmethyl-1H-benzimidazoles with o-aminothiophenol gave the previously unknown 3-aryl-2-(2-benzimidazolyl)-4H-1,4-benzothiazines and (or) the isomeric 2H-1,4-benzothiazines. 2-(4-Nitrophenacyl)-1H-benzimidazole and 2-phenacylbenzothiazole gave 4H-1,4-benzothiazines which are not liable to isomerize but the reaction of the first compound is complicated by a hydrolytic fission which yields 2-[2-(4-nitrobenzoylamino)phenylthiomethyl]- benzimidazole. A mixture of dimethylsulfoxide, acetic acid, and water was used as oxidant and solvent. The effect of the substituent and of the solvent on the tendency of the products to undergo prototropic isomerization in the benzothiazine ring have been studied. [ABSTRACT FROM AUTHOR]

The conversion of dihalomethylarenes to the corresponding aldehydes is accomplished conveniently by using sulfoxides as the oxygen donor under neutral conditions. [Copyright &y& Elsevier]