Sulfonyl Sultone

Carbonyl sulfonyl fluorides of the formula FC0(CF2) S02F have been prepared by electrochemical fluorination of hydrocarbon sultones (41,42). More commonly in a technology pioneered by Du Pont, perfluoroalkanecarbonyl sulfonyl fluorides are prepared by addition of SO to tetrafluoroethylene followed by isomerization with a tertiary amine such as triethylamine (43). 

Tnfluoroacetic anhydnde in a mixture with sulfuric acid is an efficient reagent for the sulfonylation of aromatic compounds [44] The reaction of benzene with this system in nitromethane at room temperature gives diphenyl sulfone in 61% yield Alkyl and alkoxy benzenes under similar conditions form the corresponding diaryl sulfones in almost quantitative yield, whereas yields of sulfones from deactivated arenes such as chlorobenzene are substantially lower [44] The same reagent (tnfluoroacetic anhydride-sulfunc acid) reacts with adamantane and its derivatives with formation of isomeric adamantanols, adamantanones, and cyclic sultones [45]... 

In Section 8, in discussing substitutions at sulfenyl sulfur, we noted some of the uncertainties that can complicate the use of / Nu- and / -values to deduce information about the extent of bond making and bond breaking in the rate-determining transition state. For substitutions at sulfonyl sulfur Deacon et al. (1978) have been able to examine a system, the opening of the ring in sultones [79] by phenoxide ions (159), where the most serious of these... 

We discussed earlier (p. 135) that nucleophilic substitution at the sulfonyl group of the cyclic, five-membered sultone [55] occurs over 10J times faster than for an open chain aryl arenesulfonate and that this large rate acceleration... 

Much research has been done on the synthesis of perhalogenated P-sultones. The sulfonation of acyclic fluorovinyl ethers leads to a product that is stable up to slightly above room temperature. Thermolysis decomposes the ring structure under SO2 evolution and formation of acid fluorides and perfluorocyclopropane (Eq. 78). )S-Sultones have been synthesized by addition of sulfonyl chlorides to perhalogenated ketones in the presence of triethylamine. The formation of the l-oxa-2-thiacyclobutane 2,2-dioxides appears to require an activated but sterically unhindered carbonyl group because acetone, chloroacetone, trifluoroacetophenone, and p-nitroaceto-phenone did not yield the desired products. ... 

Ring-closing metathesis methodology has been used to access 7-membered ring sultones (e.g. 278, n = 1, m = 1) efficiently from the acyclic diene precursor 277, which could readily be made in turn fom the appropriate olefinic sulfonyl chloride and alcohol [02SL2019]. 

The unsaturated sultones 82 were also formed from 81 (prepared in turn by esterification of the alcohol 80 with the sulfonyl chloride 79) using Grubbs imidazolidine — based ruthenium catalyst <03SL667>. 

The reaction of epoxy sulfonyl chlorides 136 with triethylamine is thought to proceed through intermediate epoxy sulfenes 137 to give the 5/7-1,2-oxathiole 2,2-dioxides 138 (Equation 26) <1998SL1411>. The interaction of phenylmethanesulfonyl chloride with triethylamine, 2,4,6-trimethylpyridine A -oxide, and an alkene probably involves epoxidation of phenylsulfene to give the hitherto unknown oxathiirane 3, 3 -dioxide (a-sultone) 139 which then adds to the alkene to afford the products 140 (Scheme 6) <2000CC189>. 

Epoxysulfonyl chlorides. Obtained by epoxidation of the unsaturated sulfonyl chlorides the reactive reagents are transformed into cyclic sultones. The hydrolytic instability of the sulfonyl chlorides limits the epoxidizing agent. 

P-Lactams 28 were obtained from reaction of acylhydrazones with chloroacetyl chloride . A -Alkylation of acridine derivatives with 1,3-propane sultone gave 29. P-Phenethylamides gave 3,4-dihydroisoquinolines and N-sulfonyl gave isoquinolines 30. Nucleophilic substitution of 4-bromoisoquinoline gave the corresponding 4-substituted isoquinolines. o-Bromobenzaldehyde was reacted with allylamine and then homophthalic anhydride to afford 31. ... 

Tetrafluorethylene reacts with SO3 to form a cyclic sultone. After rearrangement, the sultone can then be reacted with hexa-fluoropropylene epoxide to produce sulfonyl fluoride adducts, where... 

In Chapter 27, King et al. present their work on determining reaction mechanisms for reaction of nucleophiles with sulfonyl chlorides. Many of the same phenomena observed for the more familiar nucleophilic attack at carbon are seen. Evidence is presented for pentavalent intermediates, direct displacement, elimination-addition (through sulfenes, C = S02), neighboring-group participation (through a (3-sultone), and return processes. 

Sulfenes when generated in the presence of tricarbonyl partners give rise to 1,3,4-dioxathiane S,S-dioxides <82AP(315)57>. Typically, the treatment of propane-2-sulfonyl chloride (305) with tri-ethylamine in the presence of 1,2,3-indanetrione (307) gives initially the )S-sultone (308) that arises by cycloaddition of the intermediate sulfene (306). Thereafter, attack by chloride ion on (308) furnishes the jS-chlorosulfonate (309). At the same time, further cycloaddition occurs with excess of (307) to generate the doubly spirocyclic 1,3,4-dioxathiane dioxide (310) (Scheme 46). 

Hanefeld and coworkers179 have recently noted that the reaction of sulfenes generated in situ from sulfonyl chlorides and tertiary amines, with vicinal tricarbonyl compounds such as indan-l,2,3-trione, alloxane, diethyl mesoxalate and 1-methyl-1,2,3,4-tetrahydroquinoline-2,3,4-trione, afford products derived mainly from ring opening of /i-sultones (equation 139). 

Koch and Peters have shown that suUenes, the sulfonyl equivalents of ketenes, can also be utilized in formal [2+2] cycloadditions to form enantioenriched p-sultones [78]. The sulfene component 173 was generated from the requisite sulfonyl chloride 172 using a non-nucleophilic amine base. 

The key sequence began with the formation of the sultone derived from the advanced homoaUyhc alcohol 15, where sulfonylation and subsequent RCM with [Ruj-II afforded sultone 18, bearing the necessary C9-C10 Z-olefin, as a single diastere-omer in 70% yield over two steps (Scheme 4.6). Subsequent alkylation of the sultone with l,l-dimethoxy-3-iodopropane, furnished sultone 19 as a 1 1 mixture of diastereomers at Cll. Construction of the dienoi commenced via deprotonation of 19 with n-BuIi, followed by addition of lCH2MgCl (supplying the C20 terminal methylene group), yielding the desired Z-dienol 20 in 60% yield [5, 6]. 

Overall, the constmction of sultones via sulfonylation/RCM from the corresponding allylic alcohol fulfills the requirements of an effective temporary tether in synthesis. The sultone functionahty provides sufficient reactivity under basic conditions to afford complex Z-substituted 1,3-dienols after the facile removal of the sulfonyl through the extrusion of SO2. The prospect of utilizing additional selective reaction pathways has the potential to generate new synthons furnishing a variety of pathways to biologically active natural products [8, 10]. 

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