Alkyl sulfonates conversion

Alkyl sulfonates are very effective cationic initiators of e-caprolactone, although only the more reactive methyl triflate and methyl fluorosulfate result in a high conversion. The mechanism of polymerization in the presence of these initiators is believed to involve methylation of the exocyclic carbonyl oxygen, followed by partial ring opening of the activated lactone by the counteranion (Fig. 

A class of enzymes capable of removing sulfur from alkane sulfonates exists, which may have relevance in microbial desulfurization of alkyl sulfides. A gene cluster ssuEADCB was identified in E. coli. The enzyme SsuD was capable of conversion of pentane sulfonic acid to pentaldehyde and sulfite. It was reported to be capable of conversion of alkyl sulfonates from C2 to CIO, as well as substituted ethanesulfonates and sulfonated buffers. The SsuE was a flavin-reducing enzyme that provided FMNH2 to the SsuD. 

Alkyl halides and alkyl sulfonates have been generally used as alkylating reagents. An example of the conversion of an alcohol into a primary amine by the Gabriel synthesis is shown in Scheme 37. ... 

The alkyl sulfonic acid bearing polysiloxane is also used as a support for powder type precious metal catalysts 2 (particle size < 200 pm) that can be used in hydrogenolysis reactions. The conversion of 1 -phenylethanol to ethylbenzene proceeds quantitatively (>99%) with the same rate as achieved with the combination of H2SO4 and a Pd/C catalyst. Therefore,... 

Dye conversion method is based on the solubilization in surface chemistry. For example, dye conversion method had been used in the testing of alkyl sulfonate, sulfate, and fatty amine. Common indicators include methylene blue, pinacyanol, and bromophenol blue [11-14]. 

The potential of alkyl-sulfonated diphosphane ligands associated with methylated a- and P-cyclodextrins during the reaction of rhodium-catalyzed hydroformylation of 1-decene was studied. In all cases, the presence of cydodextrins increased the conversion and the diemoselectivity, whereas the hnear-to-branched ratio of the aldehyde product decreased. The decrease in regiosdectivity was attributed to the formation of low-coordinated phosphane spedes [112]. 

The conversion of carboxylic acids into sulfones has been achieved through a multistep reaction (Scheme 5.11) [12], This approach was used to generate a number of new aryl and alkyl sulfones that were generated in good to excellent yield. The functional group tolerance of chemistry was outstanding, and a host of alkyl and heteroaromatic substrates were functionalized. 

In addition to well-known nucleophilic behavior of thiolate anions, sulfmates are also active in substitution reactions. To this end, the conversion of a primary alkyl iodide into an alkyl sulfone has been accomplished by simply stirring the sodium sulfinate salt with the alkyl halide in DMF at room temperature (Scheme 5.20) [21]. While only a few examples were described, this work demonstrates the ability of sulfinate salts to participate in nucleophilic substitution reactions. 

Substitution Reactions on Side Chains. Because the benzyl carbon is the most reactive site on the propanoid side chain, many substitution reactions occur at this position. Typically, substitution reactions occur by attack of a nucleophilic reagent on a benzyl carbon present in the form of a carbonium ion or a methine group in a quinonemethide stmeture. In a reversal of the ether cleavage reactions described, benzyl alcohols and ethers may be transformed to alkyl or aryl ethers by acid-catalyzed etherifications or transetherifications with alcohol or phenol. The conversion of a benzyl alcohol or ether to a sulfonic acid group is among the most important side chain modification reactions because it is essential to the solubilization of lignin in the sulfite pulping process (17). 

An asymmetric synthesis of estrone begins with an asymmetric Michael addition of lithium enolate (178) to the scalemic sulfoxide (179). Direct treatment of the cmde Michael adduct with y /i7-chloroperbenzoic acid to oxidize the sulfoxide to a sulfone, followed by reductive removal of the bromine affords (180, X = a and PH R = H) in over 90% yield. Similarly to the conversion of (175) to (176), base-catalyzed epimerization of (180) produces an 85% isolated yield of (181, X = /5H R = H). C8 and C14 of (181) have the same relative and absolute stereochemistry as that of the naturally occurring steroids. Methylation of (181) provides (182). A (CH2)2CuLi-induced reductive cleavage of sulfone (182) followed by stereoselective alkylation of the resultant enolate with an allyl bromide yields (183). Ozonolysis of (183) produces (184) (wherein the aldehydric oxygen is by isopropyUdene) in 68% yield. Compound (184) is the optically active form of Ziegler s intermediate (176), and is converted to (+)-estrone in 6.3% overall yield and >95% enantiomeric excess (200). 

Fig. 1. Sulfonated and sulfated acid products viscosities after 98% conversions at varying temperatures where the vertical line indicates the maximum temperature for batch sulfonation using SO to minimi2e color deterioration lines A—C represent branched C 2 alkyl ben2ene (BAB) sulfonic acid from SO, oleum (settied), and oleum (whole mixture), respectively lines D and E, lauryl alcohol 3-ethoxylate sulfuric ester (SO ) and lauryl alcohol sulfuric ester...

Toluenesulfonic Acid. Toluene reacts readily with fuming sulfuric acid to yield toluene—sulfonic acid. By proper control of conditions, /)i7n7-toluenesulfonic acid is obtained. The primary use is for conversion, by fusion with NaOH, to i ra-cresol. The resulting high purity i7n -cresol is then alkylated with isobutylene to produce 2 (i-dii-tert-huty -para-cmso (BHT), which is used as an antioxidant in foods, gasoline, and mbber. Mixed cresols can be obtained by alkylation of phenol and by isolation from certain petroleum and coal-tar process streams. 

In contrast to phosphorus esters, sulfur esters are usually cleaved at the carbon-oxygen bond with carbon-fluorine bond formation Cleavage of esteri nf methanesulfonic acid, p-toluenesidfonic acid, and especially trifluoromethane-sulfonic acid (tnflic acid) by fluoride ion is the most widely used method for the conversion of hydroxy compounds to fluoro derivatives Potassium fluoride, triethylamine trihydrofluoride, and tetrabutylammonium fluoride are common sources of the fluoride ion For the cleavage of a variety of alkyl mesylates and tosylates with potassium fluoride, polyethylene glycol 400 is a solvent of choice, the yields are limited by solvolysis of the leaving group by the solvent, but this phenomenon is controlled by bulky substituents, either in the sulfonic acid part or in the alcohol part of the ester [42] (equation 29)... 

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