Sodium arylsulfinates

Scheme 13 Reaction of ( )-alkenylbismuthonium salts with sodium arylsulfinates [37]...

Sodium arylsulfinates and palladium salts react to form arylpaUadium salts and sulfur dioxide. When carried out in the presence of some dienes, stable organopalladium complexes have been obtained. For example, 1,5-cyclooctadiene and sodium p-toluenesulfinate with palladium chloride yields the a,it-complex shown in equation (48).109... 

The apparent SN reactions of chlorosulfines with sodium arylsulfinates to give sul-fonylsulfines with inversion of configuration in high yield was suggested to proceed via an addition-elimination mechanism rather than an SN2 mechanism.58... 

Although the reaction of 1,2-dichloro-3,3-difluorocyclopropene with thiocyanate leads simply to the replacement of the two chlorines by the nucleophile, reaction of the cyclopropene or of tetrachlorocyclopropene with sodium arylsulfinates gave an alkene in low yield (< 10%), apparently via the cyclopropenone, e.g. reaction of I. ... 

Small amounts of water act in synergy with sonication and solid-support catalysis, for instance, in the reaction of thiocyanate ions. As in the previous case, presonication of the reagent and the support was found to improve the selectivity. These methods permit the substitution reactions to be run even in apolar solvents. Two practically simultaneous papers have described the preparation of aryl sulfones by alkylation of sodium arylsulfinates with reactive alkyl chlorides.i The reaction with benzyl chlorides is best performed on alumina, and allyl bromide reacts quantitatively in a DMF-water mixture in a few minutes. Activated primary halides undergo substitution by sodium azide in aqueous solution to give the potentially explosive organic azides. 1 The paper discusses the possible role of the relative densities of the starting material, the aqueous solution of the reagent, and the product in the success of the preparation. 

A novel and convenient Pd-catalysed desulfitative cross-coupling reaction of sodium arylsulfinates (346) with diallq l phosphites has been developed. This highly efficient method provided a rapid access to a... 

Arylalkylsulfones ate important intermediates obtained by alkylation of arylsulfinic acids. The latter ate obtained by reduction of the corresponding sulfonyl chloride. This reduction process is simple and of general appHcation involving the addition of the isolated sulfonyl chloride paste to excess aqueous sodium sulfite followed by salting-out the product and isolation. With mote rigorous reduction conditions, such as zinc/acid, sulfonyl chlorides ate reduced through to aryknercaptans, eg, 2-mercaptonaphthalene is manufactured from naphthalene-2-sulfonyl chloride. 

The cleavage of alkyl aryl sulfones by sodium amalgam and alcohols65 probably proceeds also through the intermediacy of a radical anion, followed by splitting to the arylsulfinate anion and an alkyl radical. Both the sulfinate anion and the disproportionation products of the radical have been observed. 

Arylsulfinate anions have been employed as terminators of cascade carbopalladations. Starting from an iodoaryl-substituted 1,4-cyclohexadiene, treatment with a palladium catalyst led to an intermediate rr-allyl complex, which was trapped with sodium benzene-sulflnate to yield a tricyclic allylsulfone (Scheme 31). 

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