Dimethyl sulfoxide solvent properties

Solution Properties. Lignin in wood behaves as an insoluble, three-dimensional network. Isolated lignins (milled wood, kraft, or organosolv lignins) exhibit maximum solubiUty in solvents having a Hildebrand s solubiUty parameter, 5, of 20.5 — 22.5(J/cm ) (10 — ll(cal/cm ) > and A// in excess of 0.14 micrometer where A]1 is the infrared shift in the O—D bond when the solvents are mixed with CH OD. Solvents meeting these requirements include dioxane, acetone, methyl ceUosolve, pyridine, and dimethyl sulfoxide. 

Pesticide Solvent. The majority of organic fungicides, insecticides, and herbicides (qv) are soluble in DMSO, including such difficult-to-solvate materials as the substituted ureas and carbamates (see Fungicides, agricultural Insect control technology Pesticides). Dimethyl sulfoxide forms cosolvent systems of enhanced solubiUty properties with many solvents (109). 

Powerful solvents such as dimethyl sulfoxide (common laser dye solvent) and solubilizing substituents (K" and R " = sulfoalkyl in stmcture 32) may enhance the transport of dyes in solution through skin and other membranes. Reference 88 (on laser dye solutions and toxicity) is recommended to researchers working with dye solutions. Other dyes, such as Indocyanine Green, attain useful properties (blood tracer dye) as a result of having solubilizing substituents in their stmcture. 

Several cleaning formulations for specific uses contain unreacted polyamines. Examples include mixtures of ammonium alkylbenzenesulfonate, solvents, and PIP which give good cleaning and shine performance on mirrors and other hard surfaces without rinsing (305), and a hard-surface cleaner composed of a water-soluble vinyl acetate—vinyl alcohol copolymer, EDA, cyclohexanone [108-94-1] dimethyl sulfoxide [67-68-5] a surfactant, and water (306). TEPA, to which an average of 17 moles of ethylene oxide are added, improves the clay sod removal and sod antiredeposition properties of certain hquid laundry detergents (307). 

Researchers studying polypeptide and polypeptide hybrid systems have also processed vesicles using two solvents. This method usually involves a common organic solvent that solubilizes both blocks and an aqueous solvent that solublizes only the hydrophilic block. The two solvents can be mixed with the polypeptide or polypeptide hybrid system at the same time or added sequentially. The choice of organic solvent depends heavily upon the properties of the polypeptide material, and commonly used solvents include dimethylformamide (DMF) [46, 59], methanol (MeOH) [49], dimethyl sulfoxide (DMSO) [50, 72], and tetrahydrofuran (THF) [44, 55]. Vesicles are usually formed when the organic solvent is slowly replaced with an aqueous solution via dialysis or removed through evaporation however, some vesicles have been reported to be present in the organic/aqueous mixture [49]. 

The red and orange forms of RhCl[P(C6H5)3]3 have apparently identical chemical properties the difference is presumably due to different crystalline forms, and possibly bonding in the solid. The complex is soluble in chloroform and methylene chloride (dichloromethane) to about 20 g./l. at 25°. The solubility in benzene or toluene is about 2 g./l. at 25° but is very much lower in acetic acid, acetone, and other ketones, methanol, and lower aliphatic alcohols. In paraffins and cyclohexane, the complex is virtually insoluble. Donor solvents such as pyridine, dimethyl sulfoxide, or acetonitrile dissolve the complex with reaction, initially to give complexes of the type RhCl[P(C6H6)3]2L, but further reaction with displacement of phosphine may occur. 

Solvents have been added to nerve agents to facilitate handling, to stabilize the agents, or to increase the ease of percutaneous penetration by the agents. Percutaneous enhancement solvents include dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylpalmitamide, N,N-dimethyldecanamide, and saponin. Color and other properties of these solutions may vary from the pure agent. Odors will vary depending on the characteristics of the solvent(s) used and concentration of nerve agent in the solution. 

Since the solvent properties of dimethyl sulfoxide are widely different from those of hydrocarbons and halogenated hydrocarbons, it may be difficult to compare the kinetic and thermodynamic data for the C02H group (Table 16) directly with others. However, heating the carboxylic acid (68, X = OH) in toluene affords the sp isomer almost exclusively. Probably, the observed results with the carboxylic acid derive from difficulty in the formation of a hydrogen bond owing to a steric effect, in addition to the nonplanar conformation of the carboxyl group relative to the naphthalene. 

Bell, 1989 Rhee and Bell, 1991), random copolymers of methyl acrylate and acrylonitrile were directly polymerized onto the carbon fiber surface. Dimethyl formamide, dimethyl sulfoxide and distilled water proved to be useful as solvents for this process. Polymerization can take place on the carbon fiber electrode, with initial wetting of the fiber surface leading to better adhesion of the polymer formed. The structure and properties of the polymer can be varied by employing different vinyl and cyclic monomers in homopolymerization. Chemical bond can also be formed, such as polymer grafting to the carbon fiber surface. 

Know the physical properties of the substances with which you are working. Keep in mind that some compounds (such as acetaldehyde and tritiated water) have low boiling points. Again, keep in mind that some gloves do not offer an adequate barrier to certain chemicals. Some compounds enter the body with such facility that special care must be exercised when they are in use. One example is dimethyl sulfoxide, which as a solvent facilitates the entry of many solutes into the body. There are many known cases where radiolabeled compounds contaminated individuals who failed to consider this power of DMSO as a solute vehicle. 

The main obstacle to percntaneous penetration of water and xenobiotics is the onter-most membrane of the epidermis. This is called the stratum comeum. All entry of substances through the stratum comeum occurs by passive diffusion across several cell layers. The locus of entry varies, depending on the chemical properties of xenobiotics. Polar substances are believed to penetrate cell membranes through the protein filaments nonpolar ones enter through the hpid matrix. Hydration of the stratnm comenm increases its permeability for polar substances. Electrolytes enter mainly in a nonionized form, and thus the pH of the solution applied to the skin affects permeabUity. Many hpophdic substances, such as carbon tetrachloride and organophosphate insecticides, readily penetrate the stratum comeum. Pretreatment of the skin with solvents, snch as dimethyl sulfoxide, methanol, ethanol, hexane, acetone, and, in particular, a mixture of chloroform and methanol, increases permeability of the skin (Loomis, 1978). 

Solvatochromic Approach Solvatochromic relationships are multivariate correlations between a property, usually solubility or partitioning property (see Sections 11.4 and 13.3), and solvatochromic parameters, parameters that account for the solutes interaction with the solvent. In the case of vapor pressure, the solvatochromic parameters only have to account for intermolecular interaction such as selfassociation between the solute (i.e., pure compound) molecules themselves. The following model has been reported for liquid and solid compounds, including hydrocarbons, halogenated hydrocarbons, alkanols, dialkyl ethers, and compounds such as dimethyl formamide, dimethylacetamide, pyridine, and dimethyl sulfoxide... 

The ideal solvent for electrochemical studies should satisfy a number of requirements. In addition to the properties required for any good solvent for organic chemistry, such as a high solvating power and a low reactivity towards common intermediates, solvents for electrochemical use should be difficult to oxidise or reduce in the potential range of interest. Traditionally, the recommended potential limits are +3 V (versus the SCE) for oxidations and —3 V for reductions. Also, the solvent should have a dielectric constant higher than about 10 in order to ensure that the supporting electrolyte is well dissociated. Commonly used solvents are acetonitrile (MeCN) and dichloromethane for oxidations, and MeCN, N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) for reductions. 

Solvents that meet all or most of the criteria are propylene carbonate, dimethyl sulfoxide, 4-butyrolactone, acetonitrile, sulfur dioxide, thionyl chloride, and phosphorus oxychloride. Certain other solvents, with fairly low s values, such as tetrahydrofuran, dimethoxyethane, and 1,3-oxolane are used in conjunction with a high s solvent, in order to reduce the viscosity without impairing excessively the other desirable properties of the co-solvent. All these solvents are on the List, with properties shown in the tables mentioned. Commercial implementation of such batteries has been highly successful, with energy densities of primary dischargeable batteries of 0.3 W h g 1 or 0.5 W h cm 3 and a self discharge rate of < 2% per year of the open-circuit battery being achieved. 

Assays are often performed in an aqueous medium with water as the solvent. Most drugs are organic molecules with poor water solubility. To improve solubility or at least evenly disperse the compound throughout the assay well, compounds are commonly dissolved in dimethyl sulfoxide (DMSO). DMSO has several attractive properties. DMSO dissolves organic compounds well, has a low vapor pressure to limit evaporation, and is fairly inert. Furthermore, DMSO freezes around 18 °C. A solution of a compound in DMSO can be easily frozen for long-term storage. Because high concentrations of DMSO may affect the reliability of an assay, compound solutions must be prepared such that, when mixed in the assay, the final DMSO concentration is 1% or less. 

No physical properties of 1,2 and 1,3-diazetes have been reported since they are very energtic molecules and can only be detected by spectroscopic means. On the other hand, 1,2- and 1,3-diazetidines have been found to be mostly solids, depending on their substituents. Decomposition has been observed at the melting points of many compounds, especially in the case of 1,3-diazetidines. These compounds are mostly soluble in the usual organic solvents such as ether, chloroform, acetone, etc. However, dimethyl sulfoxide (DMSO) has been used to dissolve diazetidinium salts. Diazetidine derivatives are mostly good solids that can be purified by recrystallization. Liquid compounds can be distilled under reduced pressure without decomposition. 

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