Sulfonyl chloride chemistry

General Reaction Chemistry of Sulfonic Acids. Sulfonic acids may be used to produce sulfonic acid esters, which are derived from epoxides, olefins, alkynes, aHenes, and ketenes, as shown in Figure 1 (10). Sulfonic acids may be converted to sulfonamides via reaction with an amine in the presence of phosphoms oxychloride [10025-87-3] POCl (H)- Because sulfonic acids are generally not converted directiy to sulfonamides, the reaction most likely involves a sulfonyl chloride intermediate. Phosphoms pentachlotide [10026-13-8] and phosphoms pentabromide [7789-69-7] can be used to convert sulfonic acids to the corresponding sulfonyl haUdes (12,13). The conversion may also be accompHshed by continuous electrolysis of thiols or disulfides in the presence of aqueous HCl [7647-01-0] (14) or by direct sulfonation with chlorosulfuric acid. Sulfonyl fluorides are typically prepared by direct sulfonation with fluorosulfutic acid [7789-21-17, or by reaction of the sulfonic acid or sulfonate with fluorosulfutic acid. Halogenation of sulfonic acids, which avoids production of a sulfonyl haUde, can be achieved under oxidative halogenation conditions (15). 

Arenethiols. Most of the chemistry described for alkanethiols is not appHcable to ben2enethiols and other arenethiols. The synthesis of ben2enethiol is best carried out by reduction of the ben2ene sulfonyl chloride (eq. 17). Other methods for synthesi2ing arenethiols are discussed at greater length in the Hterature (28). 

Replacement of a benzene ring by its isostere, thiophene, is one of the more venerable practices in medicinal chemistry. Application of this stratagem to the NSAID piroxicam, gives tenoxicam, 136, a drug with substantially the same activity, nie synthesis of this compound starts by a multi-step conversion of hydroxy thiophene carboxylic ester 130, to the sulfonyl chloride 133. Reaction of that with N-methylglycinc ethyl ester, gives the sulfonamide 134. Base-catalyzed Claisen type condensation serves to cyclize that intermediate to the p-keto ester 135 (shown as the enol tautomer). The final product tenoxicam (136) is obtained by heating the ester with 2-aminopyridine [22]. 

The most direct approach to the four-membered S-ring is cycloaddition of sulfenes to alkenes. The sulfenes are generated in situ by base-induced de-hydrohalogenation of sulfonyl chlorides. Because of their special susceptibility to cycloaddition reactions, research into the chemistry of sulfenes is expanding. 

This molecule is unstable, with incredibly high maximum rates of temperature and pressure rise calorimetrically determined (14,000°C and 1,500 bar per min) even though dissolved in a solvent. Several pages of computerised fantasy over the heat of decomposition, based solely on identified, but unquantified, volatiles while neglecting the black tar which is probably the major product, leave readers no wiser as to the circumstances. The original reactor-burst during manufacture from the alcohol and the sulfonyl chloride in the unspecified solvent should have started at around room temperature this formation reaction is presumably exothermic. The usual solvents for such reactions, tertiary amines, would also be important reagents in decomposition chemistry. 

Arylsulfonyl chlorides are pivotal precursors for the preparation of many diverse functional types including sulfonate esters,8 amides,4 sulfones,9 sulfinic acids,10 and others.11 Furthermore, sulfonyl fluorides are best prepared from sulfonyl chlorides.12 The sulfonyl fluorides have many uses, among which is their utilization as active site probes of chymotrypsin and other esterases.13 The trifluoromethyl group also plays valuable roles in medicinal chemistry.14... 

The reaction has been extensively applied to the synthesis of precursors of dendrimers. Due to the possibility of converting the obtained thiol directly to sulfonyl chlorides, Percec widely investigated this chemistry for the preparation of multisulfonyl chlorides [33]. These compounds exhibit important applications in synthetic and supramolecular chemistry (Scheme 37). 

Of the many known fluorophores, only a few are routinely employed for immunofluorescence. Spectral maxima for such fluorophores are provided in Table 1. Conjugation of the fluorophores to antibodies is typically achieved through reactive isothiocyanate, sulfonyl chloride, or succinimidyl ester groups, which provide bonding to protein amines. Since most investigators purchase fluorophores already conjugated to antibodies, the chemistry of these and other reactive groups will not be further addressed (see Chapter 6 for details). Additional fluorophore information is summarized below. 

Activation with sulfonic acid chlorides is more general, rendering amides with the possible participation of symmetric anhydrides after disproportionation. This method has also found use in the synthesis of modem 3-lactam antibiotics. However, in peptide chemistry this activation method leads to unwanted side reactions, like formation of nitriles in the cases of glutamine and asparagine, and racemization. In a convenient one-pot procedure, the carboxylic acids are activated by sulfonyl chlorides under solid-liquid phase transfer conditions using solid potassium carbonate as base and a lipophilic ammonium salt as catalyst. ... 

In aliphatic chemistry replacement of a hydrogen atom by the sulfonyl chloride group is achieved mainly by Reed s process,197 which involves simultaneous action of sulfur dioxide and chlorine ( sulfochlorination )198 on the hydrocarbon according to the total reaction ... 

N-Arylsulfonamides are an important class of therapeutic agents in medicinal chemistry. Traditional preparation involves reaction of sulfonyl chlorides with amines, but the sulfonation of weakly nucleophilic amines is difficult. Pd catalysis proved to be effective for N-Arylation of sulfonamides with 4-chloroquinoline (Scheme 10.32) [71]. 

The field of organic chemistry has seen the most extensive use of polymeric materials as aids in effecting chemical transformation and product isolation. Insoluble polymer supports have been used as handles to facilitate these functions. As chemical reagents can be bound to an insoluble polymer carrier and used in organic synthesis [117,118], polymer-bound reagents can also be used to assist in the purification step of solution-phase reactions [119,120]. The latter are known as scavenger resins. These are added to the reaction mixture upon completion of the reaction in order to quench and selectively bind to the unreacted reagents or by-products. The polymer-bound impurities are then removed firom the product by simple filtration to obtain pure compounds. For example, aminomethylated poly(styrene-co-divinyl benzene) can be used to remove acid chlorides, sulfonyl chlorides, isocyanates, thiocyanates, and proton. Similarly, 2-Chlorotrityl resins have been developed for the attachment of carboxylic acids, alcohols. 

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