Sulfonyl halides compounds

It has been reported that the reactions of 2-aminothiazoles and sulfonyl halides generally afford mono sulfonyl and disulfonyl (171) compounds (Scheme 109) (355-362). Angyal (358) explained this result by a mechanism where in. the first reaction the product would be the cation (172)... 

Oxidation of 2-mercapto-l,2,4-triazolo[l,5-c]pyrimidines (174) with chlorine or bromine in water (64BRP951652 65JCS3369), with hydrogen peroxide and chlorine (95MIP1), as well as with sodium chlorate in hydrochloric acid (94JMC2371) gave the corresponding 2-sulfonyl halide derivatives 175. Oxidation of the 2-alkylmercapto compounds 176 to the 2-alkylsufonyl derivatives 177 was made with ammonium peroxodisulfate and sulfuric acid... 

The initiator in ATRP is usually a low molecular weight activated organic halide (RX, R=aclivated alkyl, X=chlorine, bromine, iodine). However, organic pscudohalidcs (e.g, X=thiocyanatc, azide) and compounds with weak N-X (e.g. N-bromosuccinimide 7 ) or S-X (e.g. sulfonyl halides - see below) have been used. 

Normally, reactive derivatives of sulfonic acids serve to transfer electrophilic sulfonyl groups259. The most frequently applied compounds of this type are sulfonyl halides, though they show an ambiguous reaction behavior (cf. Section III.B). This ambiguity is additionally enhanced by the structure of sulfonyl halides and by the reaction conditions in the course of electrophilic sulfonyl transfers. On the one hand, sulfonyl halides can displace halides by an addition-elimination mechanism on the other hand, as a consequence of the possibility of the formation of a carbanion a to the sulfonyl halide function, sulfenes can arise after halide elimination and show electrophilic as well as dipolarophilic properties. 

As a consequence of facile homolytic cleavages, sulfonyl halides (I > Br > Cl F unsuitable) are able to add to unsaturated C—C systems. To prevent (or reduce) competing polymerizations, the additions of sulfonyl chlorides have been recommended to be carried out in the presence of copper(I/II) salts (Asscher-Vofsi reaction ). Comprehensive surveys have been published on the resulting j8-halogeno sulfones (or their vinyloguous compounds) as well as on their dehalogenation products (vinyl sulfones, 1-sulfonyl-l, 3-dienes, etc.). Table 5 reviews a series of sulfonyl halide additions and facile hydrogen halide eliminations. 

Reaction between sulfonyl halides and ammonia or amines 3-17 Vicarious substitution of aryl nitro compounds... 

Sulfonimidothiazolines, 317, 318 Sulfonyl halides, with 2-aminothiazoles, 69 Sulfur (Sg), in synthesis of, A-4-thiazoline-2-thione, 373 Sulfur compounds, 69 Sulfuric acid, with alcohols, 38, 47, 80, 90 in bromination, 77 dealkylation by, 39 deuterated, 92 diazotization with, 66 in nitrations, 72 rearrangements in, 73, 113 Sulfuryl chloride, 432 Symbiotic behavior, see HSAB theory Symmetry. C2v and C2p, 120 Synthetic fibers, 154... 

A variety of sulfur compounds are converted directly to sulfonyl halides by the action of bromine or chlorine water. The list includes mer-captans, sulfides, disulfides, thiol esters, thiocyanates, alkyl xanthates, and S-alkylthiouronium salts. Chlorination of the thiouronium salts sometimes leads to highly explosive products. Most of the reactions occur at low temperatures and give excellent yields of sulfonyl chlorides. The corresponding bromides are formed in somewhat lower yields (36-67%). Under anhydrous conditions halogenation of disulfides gives sulfenyl halides, viz., RSSR + Xj — 2RSX. 

The replacement of a hydrogen atom on an aromatic nucleus by the sulfonyl halide grouping in a one-step process is accomplished by treat-ing the aromatic compound with chloro- or fluoro-sulfonic acid. Two equivalents of the halosulfonic acid are required, and frequently three equivalents are used. The aromatic sulfonic acid is presumably an intermediate in the process and is converted to the sulfonyl halide by the second equivalent of halosulfonic acid (cf. method 540). Reaction usually occurs at -5° to 30° in chloroform or carbon tetrachloride solution. 

Action of Grignard Compounds on Sulfonyl Halides and Sulfonates. 

Zinc salts of sulfinic acids are formed by reduction of sulfonyl chlorides by zinc and hot water. The zinc salts may be converted to sodium salts by the action of sodium carbonate. Over-all yields of the sodium salts of -toluenesulfinic acid and 2-dibenzofuransulfinic acid are 64-67%. Equally good results have been obtained by reduction of sulfonyl halides with aqueous sodium sulfite. Complete reduction to sulfhydryl compounds occurs with certain reducing agents (method 509),... 

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