Experimental procedures sulfone

Experimental Procedure. Morwell brown coal was solubilised by reacting with phenol, in the presence of para toluene sulfonic acid, at 1830C, and the reaction product was then separated into four fractions and analysed according to procedures described elsewhere (lj. The structural characteristics of the four fractions as determined by the present work and confirmed by reference to the literature ( ,3) are summarised in Table I. As these characteristics are influenced to some extent by the presence of chemically combined phenol, the content of this in each fraction is also estimated. 

Provided the described experimental procedure is followed, there seems to be little restriction in the use of the analysis. Typical data obtained by conductometric titration for the sulfonate contents of a variety of pulps and lignin are shown in Table 7.7.1 along with data obtained by other methods. 

Experimental. The sulfonated polystyrene (SPS) was obtained from Dr. Robert Lundberg of the Exxon Research and Engineering Company, and was prepared by procedures described elsetdiere[34]. The sample used in this study had 5.6 percent of the styrene repeat units sulfonated. The acid SPS was neutralized with 95% of the stoichiometric amount of nickel acetate in tetrahydrofuran/water solution, precipitated into water, then dried under vacuum at 120 C. 

A MW-assisted protocol for the synthesis of azides, thiocyanates, and sulfones has been developed (Scheme 12) that has proved to be a useful alternative, as the use of environmentally deterimental volatile chlorinated hydrocarbons is avoided.All the reactions with these readily available halides or tosylates have shown significant increase in reactivity, thus reducing the reaction times with substantial improvement in the yields. Various functional groups such as ester, carboxylic acid, carbonyl, and hydroxyl were unaffected under the mild reaction conditions employed. This method involves simple experimental procedures and product isolation which avoids the use of phase-transfer catalysts, and is expected to contribute to the development of greener strategy for the preparation of various azides, thiocyanates, sulfones, and other useful compounds. 

Recently a University of Texas group synthesized a number of isomerically pure alkyl aryl sulfonate surfactants (8) which are structurally similar to components of practically important petroleum sulfonate surfactant products (8, 9). The Texas group established (9 ) and we confirmed (10) that ultralow tensions can be achieved with certain of these pure surfactants, provided the right combination of surfactant concentration, sodium chloride concentration, hydrocarbon, temperature and experimental procedure is employed. 

Experimental Procedure Before the electrolysis, a solution of trifluoromethane-sulfonic acid in methanol (0.125 M, 0.5 ml) is introduced at the inlet to fill the anodic and cathodic chambers. After that, a 0.05 M solution of p-methoxytoluene (31 mg, 0.25 mmol) in methanol (5 ml) is fed into the inlet of the anodic chamber (flow rate 2 ml/h). The electrolysis is carried out under constant current conditions (11mA, 4.0 F/mol and 22 mA, 8.0 F/mol based on the amount of p-methoxytoluene) at room temperature (cooled in a water bath). The outlet solution is discarded until it becomes neutral, and then the aliquots (1 ml) of the outlet solution are collected at intervals and analyzed by GC to determine the amount of the product, p-methoxybenzaldehyde dimethyl acetal. For preparative purpose, the outlet solution is collected in a flask and the product is isolated using a conventional technique. 

Sulfonic acid groups (SO3H) are both bulky and electron-withdrawing consequently once one sulfonic acid group has been introduced into the aromatic nucleus, the resultant arylsulfonic acid will be more resistant towards further sulfonation. The latter will require more drastic conditions and the product will contain the two sulfonic acid groups in the 1,3-position with respect to each other. With reactive substrates, e.g. aromatic hydrocarbons, halides or ethers, mono-chlorosulfonation is often best achieved at low temperature in ftie presence of chloroform, dichloromethane or 1,2-dichloroethane to moderate the reaction and avoid disulfonation. Suter and Weston S described the experimental procedures for the sulfonation of aromatic hydrocarbons, halides and ethers and many early references and details of the synthesis of sulfonic acids and sulfonyl chlorides are included in Suter s comprehensive text." ... 

Tables 3 6 give a survey of literature data for the vapor-liquid equilibrium of aqueous solutions of a single polyelectrolyte with various counterions. Abbreviations (shown in Table 2) are used to characterize the polyelectrolyte and the experimental procedures (MO membrane osmometry DMO differential membrane osmometry VO vapor pressure osmometry ISO isopiestic experiments EMF electromotive force measurements including also measurements with ion-selective electrodes as well as titration FPD freezing point depression GDM gel deswelling investigations). Table 3 gives a survey for aqueous solutions of poly(styrene sulfonic acid).

The transformation from arenes into phenol acetates can be achieved with hypervalent iodine compounds (such as phenyliodonium acetate, PhI(OAc)2), with chromates, or under aerobic conditions. Ligands, like picolinic acids, stabilize the intermediate palladium(IV) salts. In the presence of Lewis acids or silver salts, biaryl formation takes place. The influence of different directing groups has recently been reviewed. For example, diaryl sulfones or sulfoxides having at least one heteroaryl attached can be oxidized to the corresponding aryl acetates (Scheme 5-194, Experimental Procedure below). ... 

These reactions are useful because they run under mild conditions, use inexpensive or easily recoverable starting materials, and have short reaction times. The major problem in purification is the separation of the sodium pyridone sulfonate from excess sodium sulfite, sodium bromide, and sodium bromoalkyl sulfonate. However, these latter compounds usually would not interfere with the use of the pyridone sulfonate as a water tracer. From a practical point of view, the pyridone sulfonates need not be purified, but can be used directly. A modified synthetic procedure involves the treatment of the pyridone sodium salt with a tenfold excess of a,iu-dibromoalkane in acetonitrile, followed by removal of the excess dibromide by vacuum distillation. The resulting product is treated with an excess of sodium sulfite in aqueous ethanol. Evaporation of the solvent yields a useful tracer. Procedures given in the experimental section were... 

The use of furylhydroperoxides[1] has facilitated an operationally simple procedure, alternative to the one reported by Kagan[2]. Oxidation takes place rapidly and very high e.e.s have been obtained, especially in the case of aryl methyl sulfides, while overoxidation to sulfone can be reduced to a great extent (<3 %) under the proposed experimental conditions. 

Fig. 17. 0=S=0 bond angles Inland S=0 bond lengths (r) in XSO2Y sulfones Circles experimental values (for sources see Table 5 and Ref. The empirical relationship 31 = -147.7r + 331.7 was found by a least squares procedure the trigonometrical expression utilizes the remarkable phenomenon of the O O distance being constant (2.484 A) in a large series of sulfone molecules...

Window diagrams and related methods may in principle be applied to optimization problems in more than one dimension. The main difference compared with one-parameter problems is that graphical procedures become much more difficult and that the role of the computer becomes more and more important. Deming et al. [558,559] have applied the window diagram method to the simultaneous optimization of two parameters in RPLC. The volume fraction of methanol and the concentration of ion-pairing reagent (1-octane sulfonic acid) were considered for the optimization of a mixture of 2,6-disubstituted anilines [558]. A five-parameter model equation was used to describe the retention surface for each solute. Data were recorded according to a three-level, two-factor experimental... 

The synthesis of the [2.2]paracyclophanes 59, 60, 62, 64, 66, and 68 containing the tetracyanobenKne-moiety and different donor-substituents required due to the extremely low volatility of the corresponding sulfones a modification of the experimental standard-procedure (cf. Sect. 3.1.2) [18]. 

Experimental Materials and Procedure The equilibrium adsorption of sodium dodecylbenzene sulfonate (SDBS), and deoiled TRS 10-410 (a commercial petroleum sulfonate with an equivalent weight of 418) on silica gel (Davison Grade 62), and crushed Berea sandstone was measured at 30°C at two brine concentrations (0 and 1 wt.% NaCl). 

One of the earliest of the water soluble calixarenes was made by sulfonation of the upper rim, and this remains a frequently used procedure. Experimental details have been reported for the sulfonation of jh 4S9c 0H 4S9c... 

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