Hexanesulfonic acid

Orga.nic Chemistry. The organic chemistry of sulfur dioxide, particularly as it relates to food appHcations, has been discussed (246). Although no reaction takes place with saturated hydrocarbons at moderate temperatures, the simultaneous passage of sulfur dioxide and oxygen into an alkane in the presence of a free-radical initiator or ultraviolet light affords a sulfonic acid such as hexanesulfonic acid [13595-73-8]. This is the so-called sulfoxidation reaction (247) ... 

Diethanolamine can be determined in workplace air by drawing the air sample through aqueous hexanesulfonic acid and analysing by ion chromatography. The limit of detection for this method is 13 j,g per sample (Eller, 1994). 

HCIO4 extn, SPE cleanup, 1-hexanesulfonic acid addn, online trace enrichment on Inertsil Cg, 5 m, preconcn column and switching to analytical column... 

There is no clear preference for either methanol or acetonitrile as organic modifier in the mobile phase. Nevertheless, addition of alkylsulfonic acids in the mobile phase has been employed to alter the retention and improve the peak shape and separation of trimethoprim and sulfonamides ion pairs. Pentanesulfonic acid (216), hexanesulfonic acid (275), or octanesulfonic acid (238) are tire alkylsulfonic acids used in the analysis of these drugs. 

Isocratic acetonitrile + phosphate-ammonium hydroxide buffer, pH 3.60 containing 0.90 g/L 1-hexanesulfonic acid (9.0 + 91.0 v/v). 

Premix buffer concentrate (concentration 17.5 mM sodium acetate, 33 m M acetic acid, 10 mM hexanesulfonic acid sodium salt) is purchased from the manufacturer. Reservoir A 25 ml premix buffer added to 1 liter solvent A3 (3.5% v/v tetrahydrofuran in water). Reservoir B 88% acetonitrile/12% isopropanol, v/v (solvent B2). 

Fig. 5-26 shows the separation of mono-, di-, and triethylamine, accomplished by using octanesulfonic acid as the ion-pair reagent. The less-hydrophobic hexanesulfonic acid is used in combination with boric add as the eluent for the separation of ethanol-amines, as shown in Fig. 5-27. These compounds are detected by measuring the electrical conductance, thus the background conductance is generally lowered with a membrane suppressor. The addition of boric acid to both the eluent and the regenerent serves to enhance the sensitivity for di- and triethanolamine.

Quaternary ammonium compounds can be analyzed under similar chromatographic conditions, but without adding boric acid. This includes choline (2-hydroxyethyl-trime-thylammonium hydroxide), which is commonly found in fauna and flora as a basic constituent of lecithin-type phospholipids. The ion-pair chromatographic separation of choline requires an eluent that, in addition to hexanesulfonic acid as the ion-pair re-... 

Fig. 5-27. Separation of ethanolamines. — Separator column IonPac NS1 (10pm) eluent 0.004 mol/L hexanesulfonic acid + 0.04 mol/L H3B03 flow rate 1 mL/min detection suppressed conductivity injection volume 100 pL solute concentrations ammonium (1), 2.5 ppm monoethanol-amine (2), 5 ppm diethanolamine (3), and 10 ppm triethanolamine (4).

Fig. 5-28. Analysis of choline and chlorocho-line. - Separator IonPac NS1 (10 pm) eluent 0.002 mol/L hexanesulfonic acid / acetonitrile (97 3 v/v) flow rate 1 mL/min detection suppressed conductivity injection volume 50 pL solute concentrations 10 mg/L each of choline chloride and chlorocholine chloride.

Patel, R. M., Benson, J. R. and Hometchko, D. 1990. Solid-phase extraction of amphetamine and methamphetamine using polymeric supports and hexanesulfonic acid as the ion-pairing reagent, LC-GC, 8 153-158. 

Aqueous extracts (0.1 mol L NaOH) were analyzed by SEC-UV-ICP-MS (Superdex peptide HR 10/30 column, CAPS 10mmolL pH 10.0) methanol-chloroform-water (12 5 3) extracts or enzymatic digests (proteinase K, protease XIV) analyzed by IP-HPLC-ICP-MS [Altima Cg, 5 mmol citric acid, 5 mmolL hexanesulfonic acid, pH 4.5)-methanol (95 5)] ESI-MS and ESI-MS-MS used for species identification and/or confirmation... 

IP-HPLC (hexanesulfonic acid) with UV (254 nm) and ICP-MS detection ESI-MS and MS-MS used for identification/ confirmation of Se species... 

In CE, the electrophoretic selectivity can be mitigated by judicious choice of organic additives. In the top, the mixture of eight synthetic 12mers (sequence shown bottom) is analyzed under different conditions (top panel) 50 mM phosphate buffer, pH 2.0 (middle panel) 50 mM phosphate, pH 2.0 + 100 mM hexanesulfonic acid (HAS) (bottom panel) 50 mM phosphate, pH... 

PIC A is tetrabutylammonium sulfate PIC B5 is pentanesulfonic acid PIC B6 is hexanesulfonic acid PIC B7 is heptanesulfonic acid PIC B8 is 1-octanesulfonic acid PIC D4 is dibutylamine phosphate... 

Recombinant hirudin CZE 50-mM sodium phosphate, 40-mM aminoethanesulfonic acid, 25-mM hexanesulfonic acid, 10-mM sodium borate, 2-mM tetramethylammonium sulfate, 1-mM diaminopentane (pH 7) Uncoated... 

Ion-pairing reagents such as hexanesulfonic acid can be added to the micellar separation media to modify the interaction between ionic analytes and micelles. A cationic ion-pairing agent will enhance the interaction between anionic analytes and anionic micelles. 

Ethanolamine, diethanolamine, and triethanolamine were resolved on a C g column (luminol/hydrpgen peroxide postcolumn chemiluminescence suppression detection) using an aqueous 2 mM hexanesulfonic acid mobile phase [1576]. Elution was complete in IS min. Detection limits of 0.2-1.2 nmol injected (S/N = 2) were reported (analyte dependent). 

Draw the structure of hexanesulfonic acid, 3-methylbutanesulfonic acid, and 2-chlorobutanesulfonic acid. Of these three, indicate which may be the stronger acid. 

Write out a reaction sequence that generates 4-methyl-l-cyclo-hexanesulfonic acid from toluene. 

Figure 651 Separation of various six-mem-bered sulfonium salts on Inertsil ODS II, 5 pm. Eluent 2 mmol/L hexanesulfonic acid/MeCN (90 10 vM flow rate 0.8 mt/min detection ...

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