Hydrogen chloride thietane

Cis- and frans-3-f-butyl (or 3-p-chlorophenyl) thietane 1-oxides are isomerized on treatment with hydrogen chloride in dioxane. Mixtures of varying isomer composition yield equilibrium mixtures consisting of 85-100% of the cis isomer. A similar result is obtained by heating the sulfoxides at 170-175° in decalin. Likewise, 3-methyl-3-phenylthietane 1-oxide may be isomerized to an equilibrium mixture consisting mainly (74%) of the equatorial, c/s-3-phenyl isomer. ... 

The first synthesis of thiete 1,1-dioxide 248 was achieved by elimination of hydrogen chloride from 3-chlorothietane 1,1-dioxide. The overall synthesis from epichlorohydrin (chloromethyloxiran) has been improved in several details. 3-Bromothietane 1,1-dioxide ha.s been obtained by direct bromination of thietane hl-dioxide " and the 3-chloro-derivative has been obtained similarly. " ... 

Chloropropyl thioesters are formed by the reaction of thietan with acid chlorides. Hydrogen chloride alone gave a small amount of 3-chloro-propanethiol at room temperature but polymeric material at 30—100 Charge-transfer complexes of thietan with electron-acceptors such as maleic anhydride, tetranitromethane, or tetracyanoethylene are believed to be intermediates in polymerization. The cationic polymerization of 3,3-dimethylthietan has been described. Treatment of 2-thietanones with MeCOSCl gave l,2-dithiolan-3-ones. ... 

Both anhydrous and hydrated sodium or potassium sulfide in ethanol have been used in the synthesis of thietanes. A common procedure is to use a solution of sodium or potassium hydroxide saturated with hydrogen sulfide. Liquid ammonia has been used as a solvent for the preparation of thietane (32%) from sodium sulfide and 1,3-dibromopropane. Phase-transfer catalysis has been used to good effect.A variation in which l,3-dichloro-3-methylbutane 3 is treated with aluminium chloride and hydrogen sulfide followed by aqueous sodium hydroxide gave 2,2-dimethylthietane 4 in 90% yield. An intermediate aluminium chloride-alkene complex, 5 or 6, was proposed. 

Thietane 1,1-dioxides undergo hydrogen-metal exchange on treatment with n-butyllithium and the resulting lithium derivative may be alkylated or acylated, as shown for sulfone 179. Trimethylsilyl or trimethylstannyl groups may be introduced via their chlorides." The metalation may be stereo-specific. ... 

The use of thioureas in the preparation of thietans has been reviewed. Thietans have been prepared by treatment of 1,3-dihalides with thiourea and base, or with hydrogen sulphide-aluminium chloride by treatment of disulphonate esters of 1,3-glycols with sodium sulphide and by treatment of 2-chloromethyl-3-phenyloxiran with sodium hydrosulphide. aa-Diphenyl-]8-propiothiolactone was obtained by cyclization of the bromomethyl ester of diphenylthiolacetic acid. ... 

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