Sulfuryl chloride adducts

In contrast to these adducts the DMF-sulfuryl chloride adduct (14) has been prepared in a pure state. 

A number of processes have been devised for purifying thionyl chloride. A recommended laboratory method involves distillation from quinoline and boiled linseed oil. Commercial processes involve adding various high boiling olefins such as styrene (qv) to react with the sulfur chlorides to form adducts that remain in the distillation residue when the thionyl chloride is redistilled (179). Alternatively, sulfur can be fed into the top of the distillation column to react with the sulfur dichloride (180). Commercial thionyl chloride has a purity of 98—99.6% minimum, having sulfur dioxide, sulfur chlorides, and sulfuryl chloride as possible impurities. These can be determined by gas chromatography (181). 

Another method that provides chlorides from alcohols with retention of configuration involves conversion to a xanthate ester, followed by reaction with sulfuryl chloride. This method is thought to involve collapse of a chlorinated adduct of the xanthate ester. The reaction is useful for secondary alcohols, including stoically hindered structures.8... 

The electrophilic nature of sulfuryl chloride is validated in a study on the chlorination of anthracene derivatives the observed substituent effects conform well with molecular orbital modeling859. Chlorination of ethyl 3,4,5-trialkylpyrrole-2-carboxylates results in a substantial amount of / -side-chain chlorinated products in addition to the expected a-side-chain chlorination860. This has been ascribed to the electrophilic nature of the reagent861 and the mechanism proposed involves an allylic migration of the halogen from the a-sigma adduct to the adjacent / -side chain. 

As in Equation (4), dibenzostiboles form similar adducts with CI2, Br2 <69JOM(l7)389> and sulfuryl chloride <77J0M(136)173>. Arsoles appear to be more sensitive to overhalogenation as ring cleavage can result (Scheme 5) <93JOM(445)7l>. 

Markovnikov Addition of Hydrochloric Acid to Alkenes. 1-Chloro-l-methylcyclohexane, the foimal Markovnikov adduct of hydrochloric acid and 1-methylcyclohexene, becomes largely predominant when Sulfuryl Chloride is the chlorine source and KIO the solid acid. The reaction at 0°C, in dry methylene chloride, is complete within 2 h (eq 10). 

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