Thietane sulfones

Practically speaking, almost all syntheses of these systems are based on the enamine-sulfene cycloaddition reaction143 250. The thietane sulfone thus obtained yields, by elimination of R2NH, the desired unsaturated, four-membered sulfone system187 189 231 250 251 (equation 87). 

Thietane sulfones are reduced to thietanes in moderate yields by lithiurr. aluminum hydride, " ° as exemplified by the conversion of 47 to 48. ° Since many thietane sulfones can be prepared by the cycloaddition of sulfenes to enamines (see Section V.3.B) this method is useful for preparing 3-amino substituted thietanes. 

Potassium or sodium permanganate yields thietane sulfones and treatment of thietane with concentrated nitric acid gives polymeric material. Less concentrated nitric acid gives the sulfones or, in the case of a spiro-dithietane, a trace of the sulfoxide-sulfone. ... 

A spirothietane sulfone-oxetane is a comonomer in the preparation of polyethers. A polymer obtained from this sulfone in a solution of bis(3,3-chloromethyl) oxetane with phosphorus pentafluoride can be spun to drawable filaments. Thietane sulfone spirocyclic carbonates may be polymerized via the carbonate group to high-molecular-weight solids said to be useful in laminating. Thietane 1,1-dioxide improves the dye receptivity of poly (acrylonitrile), viscose, cellulose acetate, and poly(vinyl chloride). It is also reported to be a stabilizer for nitric acid in oxidizer mixtures for rocket motors. 2-Methylthietane 1,1-dioxide is claimed to be superior to sulfolane (thiolane 1,1-dioxide) in the liquid extraction of aromatic hydrocarbons from mixtures with saturated hydrocarbons. " A number of bis(3,3-alkoxy) thietane 1,1-dioxides have been proposed as intermediates in the preparation of cyanine dyes useful as photographic sensitizers. " ... 

The discovery by Stork and Borowitz and Opitz and Adolph that the addition of sulfenes (RCH=S02) to enamines gives good yields of 3-aminothietane-1,1-dioxides (e.g., 132) has been extensively exploited in the synthesis of a variety of thietane sulfone derivatives. Truce, Breiter, Abraham, and Norell at about the same time showed that sulfene can add to ketene acetals to give 3,3-dialkoxy substituted thietane 1,1-dioxides (e.g., 133). The sulfenes are generated by dehydrohalgenation of methanesulfonyl chlorides with triethylamine. [Attempts to add sulfines (e.g., PhCH=SO) to enamines to give thietane 1-oxides were not successful.1 Sulfene additions have been reviewed. ... 

The use of cyclic enamines" > " " b.436,441,443,446.447, 456.457,470-480 (-g g UQ o ) or dieneamines (e.g., 141 ) yields fused bicyclic systems, although the latter may also yield bis-thietane sulfones. Enamines derived from morpholine, piperidine, pyrrolidine, and dimethylamine are most commonly used, but derivatives of diethylamine, di- -propyl-amine, piperazine, 4-benzylpiperidine, methylpyrrolidines, hexahydroazepin, N-methylaniline, and indoline have also been treated with sulfenes to give thietane sulfones. Asymmetric induction has been observed with the optically active enamine, 142. ... 

Thietane 1,1-Dioxides (Thietane Sulfones) C. From Thiete 1,1-Dioxides... 

Diels-Alder reactions of thiete 1,1-dioxides occur readily as exemplified by the syntheses of 151 ° and 152. Adducts of thiete 1,1-dioxide with tetraphenylcyclopentadienone or a-pyrone ° are thermally unstable. Thiete 1,1-dioxides also undergo 1,3-dipolar additions with diazoalkanes, (e.g., the formation of 153 from which the strained bicyclic thietane sulfone 154 is obtained) " nitrile oxides, and cycloadditions with the MA -dimethylenamine of isobutyraldehyde (e.g., the formation of 155). ° ... 

Photolysis of thietane sulfones (e.g., 169 ) also yields cyclopropanes. The need for a chromophore and a 2-substituent to stabilize an intermediate diradical has been emphasized. The sulfone 170 undergoes an unusual transformation. ... 

The stabilizing effect of a sulfone group on an adjacent anionic center facilitates ring-opening of the strained thietane sulfones under conditions where such an anion... 

Treatment of cis- or tra 5-2,4-diphenyl thietane 1,1-dioxide with t-butoxy-magnesium bromide or ethylmagnesium bromide gives sultines (cyclic sulfin-ates) in which the stereochemistry is preserved (e.g., 171) and cyclo-propanesulfinic acids (e.g., 172). Bases such as hydroxide ion or triethyl-amine cause ring-opening of 3-amino substituted thietane sulfones via an elimination reaction as shown for The... 

The unsubstituted 2-methylenethiirane (367) has been produced in several ways, including flash pyrolytic rearrangements of 3-thietanylidene and cyclo-propanethione (Eq. 116).424 The corresponding thietane sulfone extrudes S02, however (Eq. 117).425... 

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