With thietane

The three highest occupied orbitals of sulfoxides are the lone pairs ns and n0, as well as the 7iso bond210. The 1,3-dithietane 1-oxide adds a lone-pair ionization and destabilizes the n0 and nso radical-cation states compared with thietane oxide. According to a hyperconjugative MO model, the ns+ combination in 1,3-dithietane is destabilized by about leV relative to the basis orbital energy a(ns) due to the combination with the... 

Thietanonium ions have been observed quite frequently either as intermediates or as isolated stable salts. Treatment of an activated carbohydrate epimer, a constituent of the antiobiotic lincomycin, with thietane led to the sulfonium salt 190. By nucleophilic attack with acetate ions the ring could be opened and the process mentioned above repeated so that compound 191 results. ... 

When hexafluoroacetone is treated with thietane (2 1) a concerted addition results in the formation of a six-membered ring (Eq. 51). Here the excited state 205 seems to favor the formation of the six-membered ring structure 207 over the corresponding thietane derivative 206. 

Benzoyl chloride reacts with thietane giving S-(3-chloropropyl) thiobenzoate in 86% yield (71CHE557). 

Reaction of a carbenoid reagent with thietane has been found to lead to ring expansion to thiolane (81) (72JOC1721, 75BCJ1490). Atomic carbon desulfurizes thietanes in a stereoselective manner, perhaps via ylidic species (82) (73JA1547). 

Nitrenes generated from PhINTs and copper acetoacetate react with thietanes to form isothiazolidines.86 The initially formed S-N donor-acceptor complex undergoes ring expansion with retention of stereochemistry. Yields range from 56 to 76%. 

Reaction of arylchlorodiazirines with thietane gives a mixture of aryldi(3-chloropropyl)thioacetal and aryl(2-propenyl)(3-chloropropyl)thioacetal in a good yield. The reaction goes through a sulfur ylide intermediate (Scheme 6) <2001TL207>. 

Reaction of adamantylidene and phenylcarbene with thietane involves the formation of a sulfur ylide intermediate, followed by ring opening (Scheme 7) <2003TL6519>. 

Both the 2-thiahex-5-enyl and the 2-sulfonylhex-5-enyl radicals exhibit a significant preference for 5-exo cyclisa-tion to the thiophene over formation of tetrahydrothiopyran by 6-endo ring closure (Equation 144) <2000TL7987> and only at higher I2 concentration does the formation of tetrahydrothiopyrans compete successfully with thietane and tetrahydrothiophene production when methylene-intermpted dienoates 455 react with dimethyl disulfide (Equation 145) <1994TL5575>. 

The mechanism is only valid for systems which are capable of a propylene release. In contrast, the reactions of germylenes with thietane gave regular one-to-one copolymers 51 with a C—Ge—S sequence127 (Scheme 25). 

The investigation of the reaction of carbenes or carbenoid species with thietanes... 

O-Mesitylenesulfonylhydroxylamine (MSH) reacts with thietane to give the 5-amino salt 81. " An attempt to prepare a sulfilimine by treatment of 81 with a basic ion exchange resin was not successful.Chloramine-T gives the N-(p-tolylsulfonyl)sulfilimine 82. Several substituted thietanes yield the A -tosyl-sulfilimines in 56-100% yields. ... 

Mercuric chloride,mercuric bromide, and mercuric acetate form stable, solid complexes with thietanes which melt with decomposition. They are useful in the characterization of thietanes. No difficulty was experienced in the formation of complexes of 3-substituted thietanes even when the substituent was l-butyk but the 2,3-disubstituted thietane 89 did not give an isolable mercuric chloride complex. The superior complexing ability (relative to acyclic sulfides) of thietane was determined by partitioning thietane between heptane and saturated aqueous mercuric acetate. ... 

Other Lewis acids that complex with thietane are titanium tetrachloride or bromide,boron trifluoride,trimethylaluminum, and tin tetrachloride. The enthalpies of formation of the aluminum complex (— 16.04 kcal/mole) and the tin complex (— 14.2 kcal/mole) and the wavelength of the charge transfer band of the tin complex (270 nm) have been determined. The titanium tetrahalides form both a 1 1 and a 1 2 adduct (titanium halide thietane). °° Treatment of 3-methyl-thietane with aluminum chloride or tin tetrachloride yields a rubbery white soUd." "... 

The distribution coefficients for benzene and toluene with thietane 1-oxide was compared with those of other sulfoxides aqueous thietane 1-oxide has a greater extraction capacity than dimethyl sulfoxide. 

Alkylation and acylation are possible with thietane dioxides such as (170) and (171) to afford the derivatives (172) and (173), respectively (Scheme 68). 

The copyrolysis of 1,1-dimethylsilacyclobutane with thietane was investigated in more detail, with similar conclusions304. Results indicating the possible occurrence of a 2 4-2 cycloaddition between 1,1-dimethylsilene and dimethylsilanethione were also obtained (equation 207)304. 

Thietane (trimethylene sulfide) can be purchased from Aldrich Chemical Company and used without further purification. The thietane complex Re2(CO)9 (SCH2CH2CH2), which is used as the catalyst, is obtained in good yield from the reaction of Re2(CO)9(NCMe) with thietane by the published procedure ... 

The blockwise polymerization of either type of monomer can be induced by polyvinyl or polydienyl anions (A) to give AB or BAB copolymers, where B represents the poly(thioalkylene) sequences. In the thiirane case, the thiolate end group of the AB copolymer can readily be coupled with phosgene to give A(B)2A copolymers, whilst with thietanes the terminal carbanionic group can be used to initiate polymerization of vinyl monomers to give ABA or ABC block copolymers. 

Dichlorothietans may be hydrolysed on silica gel to j8-thiolactones or the chlorine atoms may be removed without ring opening by reduction with lithium aluminium hydride. An aldol condensation of an aldehyde with thietan-2-one went in low yield. j3-Propiothiolactones (thietan-2-ones) are cleaved by MeSCl and MeCOSCl to mixed disulphides of jS-mercaptocarboxylic acid chlorides. The polymerization rates of several )3-propiothiolactones substituted with an arylsulphonamido-group have been determined. ... 

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