Benzene dimethyl sulfoxide

Indium metal (0.85 g) is maintained at +15 V in a solution phase of 100 mLof 50 50 benzene-dimethyl sulfoxide (dmso). Benzene is purified as in Section A above dimethyl sulfoxide is dried over 4A molecular sieves before use. The cell is cooled in an ice bath throughout the experiment. Chlorine gas is bubbled slowly through the solution phase (about one bubble per second from a 2-mm tube) for 2 hours. At the end of this period, the solution is brown, and most of the indium has dissolved approximately 0.1 g of corroded material remains. 

Chang found that the mesylates of steroid 3-alcohols are cleaved stereospecifi-cally by potassium f-butoxide (MSA Res. Corp. material) in benzene-dimethyl sulfoxide at room temperature to the corresponding 3-aIcohols without inversion. In the examples cited olehn-formation was noted in yields of only 4 and 6%. The... 

Reaction The alkylation of carbanions plays a very important role in organic synthesis because products used as key blocks for numerous medicine and organic syntheses are obtained. Phase transfer catalysis has been proven to be the most efficient way of carrying out this type of reaction. Compared to traditional synthetic routes, it has a number of advantages it requires neither expensive bases (sodium amide, metal hydrides, etc.) nor hazardous solvents (ether, benzene, dimethyl sulfoxide, etc.), ensuring at the same time high selectivity and yields. 

A soln. of diethyl acetamidomalonate in dry benzene added under N2 with stirring during 1 hr. to a suspension of NaH in benzene-dimethyl sulfoxide. 

Bromocyclododecanone in benzene-dimethyl sulfoxide treated with Zn-powder and methyl iodide, stirred 8 hrs. at room temp, under Ng 2-methylcyclo-dodecanone. Y ca. 100%. F. e., also a,j -ethyleneketones by aldol condensation with aldehydes, and limitations s. T. A. Spencer, R. W. Britton, and D. S. Watt, Am. Soc. 89, 5727 (1967). 

Dimethyl sulfoxide with acetone, benzene, chloroform, ethanol, diethyl ether or water. 

Androst-4-ene-3,17-dione. Testosterone (0.58 g, 2 mmoles) is dissolved in a solution prepared from 3 ml of benzene, 3 ml of dimethyl sulfoxide, 0.16 ml (2 mmoles) of pyridine and 0.08 ml (1 mmole) of trifluoroacetic acid. After addition of 1.24 g (6 mmoles) of dicyclohexylcarbodiimide, the sealed reaction flask is kept overnight at room temperature. Ether (50 ml) is added followed by a solution of 0.54 g (6 mmoles) of oxalic acid in 5 ml of methanol. After gas evolution has ceased ( 30 min) 50 ml of water is added and the insoluble dicyclohexylurea is removed by filtration. The organic phase is then extracted twice with 5 % sodium bicarbonate and once with water, dried over sodium sulfate and evaporated to a crystalline residue (0.80 g) which still contains a little dicyclohexylurea. Direct crystallization from 5 ml of ethanol gives androst-4-ene-3,17-dione (0.53 g, 92%) in two crops, mp 169-170°. 

Dimethyl sulfoxide (DMSO) has been used to effect the elimination of sulfonates at elevated temperatures (see, for example, ref. 237). Benzene-sulfonates are recommended. The elimination of a variety of sulfonates proceeds readily in this medium in the presence of potassium /-butoxide. A -Compounds have been formed at 100°, but heating is not necessary. The effects of temperature change, orientation of the hydroxy group and changes in the sulfonate employed have been examined. The principal side reaction appears to be formation of the original alcohol (uninverted), particularly with equatorial mesylates at low temperatures it is minimized with axial tosylates. 

Copper-mediated coupling of the aryl iodide derived from l,3-bis(2-hydroxy-hexafluoroisopropyl)benzene with perfluorooctyl iodide gives the desired compound as a dimethyl sulfoxide (DMSO) complex [166] (equation 143) Even bromoarenes can be coupled [167] (equation 144)... 

In a 250-ml., three-necked, round-bottomed flask equipped with a mechanical stirrer, a gas inlet, and a stopper are placed 540 mg. (0.00346 mole) of a mixture of cis- and dimethyl sulfoxide (Note 3). While a slight positive pressure of argon is maintained... 

Only relatively few nucleophilic substitution reactions at sulfur proceed with retention. Oae found that (R)-(+)-methyl p-tolyl sulfoxide exchanged 180 with dimethyl sulfoxide at 150 °C much faster than it racemized thus, the exchange took place with retention. A cyclic intermediate, 136, was proposed to account for this behavior12,147. The same sulfoxide was found to react with N, JV -ditosylsulfurdiimide, 137, with either retention or inversion depending on the reaction conditions. Christensen148 observed retention in benzene whereas Cram and coworkers149 found that inversion took place in pyridine. A four-membered ring intermediate, 138, was postulated to account for the retention, whereas a... 

Dccalin (decahydronaphthalene),benzene, 1,4-dioxane, and ethanol may be used as solvents for the photolysis. In an alternative procedure, volatile materials swept from the photolysis vessel are condensed in a dry ice trap. This cold mixture is added to a flask containing a magnetically stirred solution of dimsyl anion in dimethyl sulfoxide, and fractionation at reduced pressure provides a solution of bicyclopentene in tetrahydrofuran. 

Biopract provides technological products and processes for industry, agriculture, and environment. They not only produce technical enzyme preparations but also develop enzymes for applications in agriculture, food, and textile industry as well as in environmental technologies. On the later, bioremediation has been an area of service delivery from Biopract. Their activities regards microbial preparations for the bioremediation of organic contaminants (mineral oil (MKW), polycyclic aromatic hydrocarbons (PAH), benzene, toluene, ethylbenzene, xylene (BTEX), methyl-tert-butyl ether (MTBE), volatile organic hydrocarbons (VOC), and dimethyl sulfoxide (DMSO)). 

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. 

Hong and coworkers have investigated the cycloaddition chemistry of fulvenes with a wide variety of alkenes and alkynes in great detail [191]. As one example, the reaction of 6,6-dimethylfulvene with benzoquinone is shown in Scheme 6.92. Under microwave conditions in dimethyl sulfoxide (DMSO) at 120 °C, an unusual hetero-[2+3] adduct was formed in 60% yield, the structure of which was determined by X-ray crystallography. The adduct is a structural analogue of the natural products aplysin and pannellin and differs completely from the reported thermal (benzene, 80 °C) Diels-Alder cycloaddition product of the fulvene and benzoquinone (Scheme 6.92) [191]. 

Fluorene-[2,5-di(aminoethoxy)benzene] copolymers 370a,b have been synthesized by Huang and coworkers [437,438] as precursors to the first water-soluble cationic PFs 371, 372a-c (Scheme 2.58). Whereas the neutral polymers 370a,b readily dissolve in common organic solvents such as THF, chloroform, toluene, and xylene (but not in dimethyl sulfoxide (DMSO), methanol, or water) their quaternization produces material 371, which is insoluble in chloroform or THF but completely soluble in DMSO, methanol, and water. For... 

Valentine and Curtis (1975) extended the synthetic utility of potassium peroxide by reporting the successful solubilization of K02 in dry dimethyl sulfoxide using dicyclohexyl- 18-crown-6 ([20] + [21]). Corey et al. (1975) used 18-crown-6 to solubilize KOz in dimethylformamide, dimethoxyethane and diethyl ether, whilst Johnson and Nidy (1975) reported its solubilization in benzene. A wide variety of chemical transformations have been realized with K02 complexes of crown ethers. With alkyl halides the main reaction products are peroxides, alcohols and olefins (Johnson and Nidy, 1975). Peroxides are... 

In recent years, a great diversity of structurally well-defined functionalized fullerenes has been designed and synthesized for that purpose. Some of them exhibit pronounced solubility in water (vide infra). But even for compounds being virtually insoluble in water, stable aqueous phases can be obtained in plenty of cases by diluting stock solutions of the compounds in polar organic solvents with various amounts of water. Notably, dimethyl sulfoxide (DMSO) and tetrahydro-furan (THF) have turned out to be excellent surfactants for preparing stable aqueous fullerene solutions (Angelini et al., 2005 Cassell et al., 1999 Da Ros et al., 1996 Gun kin et al., 2006 Illescas et al., 2003). Also cosolvents such as dimethylforma-mide (DMF) and methanol can be used to promote water solubility. After subsequent dilution of a saturated solution of C60 in benzene with THF, acetone and finally water, actually stable aqueous suspensions of pristine fullerene can be obtained (Scrivens et al., 1994). 

FIGURE 3 2 Solvent extraction efficiencies (EF) as functions of dielectric constants (D), solubility parameters (6), and polarity parameters (P and E -). Solvents studied silicon tetrachloride, carbon disulfide, n pentane. Freon 113, cyclopentane, n-hexane, carbon tetradiloride, diethylether, cyclohexane, isooctane, benzene (reference, EF 100), toluene, trichloroethylene, diethylamine, chloroform, triethylamine, methylene, chloride, tetra-hydrofuran, l,4 dioxane, pyridine, 2 propanol, acetone, ethanol, methanol, dimethyl sulfoxide, and water. Reprinted with permission from Grosjean. ... 

Figure 18. Correlations between the solubility of cmchonidme and the reported empirical polarity (A) and dielectric constants (B) of 48 solvents [66]. Those solvents are indicated by the numbers in the figures 1 cyclohexane 2 n-pentane 3 n-hexane 4 triethylamine 5 carbon tetrachloride 6 carbon disulfide 7 toluene 8 benzene 9 ethyl ether 10 trichloroethylene 11 1,4-dioxane 12 chlorobenzene 13 tetrahydrofuran 14 ethyl acetate 15 chloroform 16 cyclohexanone 17 dichloromethane 18 ethyl formate 19 nitrobenzene 20 acetone 21 N,N-drmethyl formamide 22 dimethyl sulfoxide 23 acetonitrile 24 propylene carbonate 25 dioxane (90 wt%)-water 26 2-butanol 27 2-propanol 28 acetone (90 wt%)-water 29 1-butanol 30 dioxane (70 wt%)-water 31 ethyl lactate 32 acetic acid 33 ethanol 34 acetone (70 wt%)-water 35 dioxane (50 wt%)-water 36 N-methylformamide 37 acetone (50 wt%)-water 38 ethanol (50 wt%)-water 39 methanol 40 ethanol (40 wt%-water) 41 formamide 42 dioxane (30 wt%)-water 43 ethanol (30 wt%)-water 44 acetone (30 wt%)-water 45 methanol (50 wt%)-water 46 ethanol (20 wt%)-water 47 ethanol (10 wt%)-water 48 water. [Reproduced by permission of the American Chemical Society from Ma, Z. Zaera, F. J. Phys. Chem. B 2005, 109, 406-414.]...

A calculated transition energy used to assess the polarity of a solvent. The solvent ionizing capability directly affects the position of a peak, easily measured, in the ultraviolet region of the spectrum of the complex of an iodide ion with 2-methyl- or l-ethyl-4-carbomethoxypyridinium ion. Water has a Z value of 94.6, ethanol has a value of 79.6, dimethyl sulfoxide s value is 71.1, and benzene has a value of 54. A similar polarity scale, known as x(30) values, is related to the Z value scale Z = 1.41 t(30) -E 6.92. See Solvent Effects... 

Local concentration of solvent molecules changes substantially. This can occur in hquid mixtures when the solute groimd and excited states are preferentially solvated by different solvent components. It has been observed in simulations of SD in water-dimethyl sulfoxide (DMSO) -, water-methanoF and n-hexane-methanol mixtures," as well as in om work in progress on SD in benzene-acetonitrile mixtures. ... 

The catalysts having the initial form of Co(acac)3 were recovered after the decomposition of peracrylic acid in benzene and dimethyl sulfoxide solution the catalyst recovered from benzene (catalyst B) could hardly be separated from the polymers, indicating a chemical bond between the catalyst and polymers. On the other hand, the catalyst from... 

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