Alkylsulphonates

Alkylsulphonate Esters. Methanesulfonate esters such as busulfan (7.72) produce clinical remission in chronic myelogenous leukaemia. Busulfan acts through an Sfj2 nucleophilic displacement and presumably crosslinks DNA, since the methanesulfonate... 

Figure 8.7—Separation of neutral species using surfactants. The lipophilic part of a surfactant, such as alkylsulphonate, can bind fairly easily to certain substrate species, S. The micelles that are formed in the process, although negatively charged, are carried towards the cathode by the strong electro-osmotic flow. (Adapted from Hewlett-Packard.)...

Low temperature influence on drainage rate is considered in [56,81-85]. The electrical conductivity dependence on temperature (including below the freezing point) has been studied by Balakirev and Tikhomirov [81,82], However, the authors have not reported quantitative data about drainage rate (though such calculations could be easily done) but it has been argued that the rate of liquid outflow decreases because of the increase in viscosity at low temperatures. The influence of low temperature on microsyneresis of low expansion ratio foams for production of frozen thermal insulators has been discussed in [56]. The electrical conductivity of 0.2% sodium alkylsulphonate foams was measured in the temperature range from 20 to 2°C. Table 5.6 presents the data of w0(f) dependence. 

Initial drainage rate of alkylsulphonate foams at various temperatures (a is the average of polyhedral (bubble) edge)... 

Fig. 7.10. Foam lifetime Xp vs. number n of carbon atoms in the alkylsulphonates homologues ...

These two examples with the homologous series of alkylsulphonates and alkylsulphates indicate the undoubted advantages of Foam Pressure Drop Technique for determining the foam stabilising properties of surfactants. This technique allows to distinguish small differences in the foam stabilising ability of surfactants. 

It has been established that the rise of the NaCl concentration in the Volgonate and NaDoS solutions leads to a decrease in surface tension and initial drainage rate and to an increase in foam dispersity and lifetime. The addition of dodecanol has the most significant effect on all foam structural parameters, rate of drainage processes and increase in bubble size. Fig. 10.12 depicts the dependence xR versus dodecanol concentration of a foam from alkylsulphonate (C = 0.2%). 

Fig. 10.12. r> vs. dodecanol concentration foaming agent commercial alkylsulphonate. 

Direct addition of an alkylsulphonate into imidazole is useful, not only to synthesize the sulphonate anion, but also different anions via metathesis in the halogen free method. For example, the alkylation of /V-alkylimida/oles such as /V-mcthylimidazolc with alkylsulphonate can be performed under solventless conditions at room temperature affording, after 48-72 h, the corresponding 1,3-dialkylimidazolium alkanesulphonate salts as crystalline solids in almost quantitative yields (5) [48], The alkane sulphonate anions can easily be substituted by a series of other anions by metathesis ... 

R2 and R4 are the same or different and each is a substituent selected from H, Cl, Q 4-alkylsulphonic acid radical or the salts thereof, sulphonamide, or C -alkyl-substituted sulphonamide radical... 

Insertions of carbon dioxide, sulfur dioxide, and sulfur trioxide yield aluminum carboxylates, sulfinates, and sulfonates, respectively. Treatment of the resulting complexes with aqueous acid yields the corresponding alkylcarboxylic, alkylsulphinic, and alkylsulphonic acids. High pressure and temperatures of 220-240°C are required for multiple insertions of CO2 to yield more than one equivalent of carboxylic acid per aluminum. Excess aluminum trialkyl must be avoided or the initially formed carboxylate is completely alkylated to a trialkylcarbinol. Reaction of EtsAl with CO2, for example, gives a 90% yield of triethylcarbinol. 

The pyridinium ylide (24) is obtained from the reaction of 8-bromotheophylline with pyridine. Alkylsulphonate salts of caffeine have been synthesized. A new purine-into-pteridine ring transformation has been discovered. For example, the quaternary salt (25) was obtained by direct alkylation of an appropriate xanthine with ethyl bromoacetate. Base-catalysed hydrolysis of (25) gave the pyrimidine (26), which could be cyclized to give the isoxanthopterin derivative (27). 

Recently, Reynolds [68] reported the preparation of poly(p-phenyl-eneterephthalamide)propanesulphonate 48 made from the PPTA polyanion and 1,3-propanesultone (Scheme 13). This polyelectrolyte can be solubilised in water to greater than 18 wt % when the amide is alkylsulphonated to 66%, but no lyotropic behaviour is observed. 

Alkanesulphonates, or alkylsulphonates, are produced since the 40 s by photochemical sulphochlorination of linear Cio-is paraffins with gaseous SO2 and CI2 at 25-40 °C with a subsequent neutralisation by aqueous sodium hydroxide [2,10, 11, 56,66] ... 

Electrochemical fluorination of carboxylic acid fluoride and chloride or alkylsulphonic acid fluoride/ chloride is carried out in anhydrous hydrofluoric acid medium at t < 19 C (or t<35°C for n-C8Hi5S02F) at a voltage of 5-12 V and electric current density of 0.02 A/m ... 

Kuwabata et al. [239] use anions with multiple sulphonate groups naphthalene mono-, di-and trisul-phonate, anthraquinone mono- and disulphoiiate, and copper phthalocyanine tetrasulphonate Their films show a small-angle diffraction peak around 20 = 3", reminiscent of the observations by Wemet el al. [225] on alkylsulphonates, and attributed to a layered structure. 

Levon et al. [335] have complexed PANI with DBSA in the solid state by an oven treatment of a powder mixture at 80 C, I00°C or 150°C. Their x-ray diffraction pattern shows little detail but indicates a repeat period of 27 A, which is taken as evidence for a layered structure, similar to one proposed for poly-pyrrole-alkylsulphonate [225]. 

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