3-Sulfolenes

Example 4.4 Butadiene sulfone (or 3-sulfolene) is an intermediate used for the production of solvents. It can be produced from butadiene and sulfur dioxide according to the reaction ... 

Pd-catalyzed reactions of sulfur-containing nucleophiles, SO2, CSj and S, were summarized in a review[101]. When 3-sulfolene (109) is treated with butadiene at I00"C, cis- and /ra j-2,5-divinyisulfolanes (110) are obtained. Under these conditions. 3-sulfolene (109) decomposes to butadiene and SOj, which react to give divinylsulfolane (I10)[I02]. Divinylsulfolane (110) can be obtained directly by the reaction of SO2 with butadiene[103]. 

Sulfolane and sulfones Sulfolane process Sulfolane-W 3-Sulfolene [77-79-2]... 

Production. Sulfolane is produced domestically by the Phillips Chemical Company (Borger, Texas). Industrially, sulfolane is synthesized by hydrogenating 3-sulfolene [77-79-2] (2,5-dihydrothiophene-l,1-dioxide) (2), the reaction product of butadiene and sulfur dioxide ... 

Sulfolene (2) is the next most commercially important sulfone after sulfolane. Besides its precursor role in sulfolane manufacture, 3-sulfolene is an intermediate in the synthesis of sulfolanyl ethers, which are used as hydrauHc fluid additives (see Hydraulic fluids). 3-Sulfolene or its derivatives also have been used in cosmetics (qv) and slimicides. Selected physical properties of 3-sulfolene are Hsted in Table 3. 

Sulfur dioxide acts as a dienophile ia the Diels-Alder reaction with many dienes (253,254) and this reaction is conducted on a commercial scale with butadiene. The initial adduct, sulfolene [77-79-2] is hydrogenated to a solvent, sulfolane [126-33-0] which is useful for selective extraction of aromatic hydrocarbons from... 

Butadiene also undergoes a 1,4-addition reaction with SO2 to give sulfolene [77-79-2]. This reaction followed by hydrogenation is commercially used to manufacture sulfolane [126-33-0] (56). 

Sulfolane (tetramethylenesulfone) [126-33-0] M 120.2, m 28.5 , b 153-154 /18mm, 285 /760mm, d 1.263, n 1.4820. Prepared commercially by Diels-Alder reaction of 1,3-butadiene and sulfur dioxide, followed by Raney nickel hydrogenation. The principle impurities are water, 3-sulfolene, 2-sulfolene and 2-isopropyl sulfolanyl ether. It is dried by passage through a column of molecular sieves. Distd... 

Twenty-five grams (0.212 mole) of 3-sulfolene, and 15.0 g (0.153 mole) of pulverized maleic anhydride are added to a dry 250-ml flask fitted with a condenser. Boiling chips and 10 ml of dry xylene are added. The mixture is swirled gently for a few minutes to effect partial solution, then gently heated until an even boil is established. During the first 5-10 minutes, the reaction is appreciably exothermic, and care must be exercised to avoid overheating. 

Sulfolene (2,5-dihydrothiophene-l,1-dioxide) EK, MCB Isopropenyl acetate MCB Dimedon EK, MCB... 

Optimum temperature for highest sulfolene yield is approximately 75°C. 

At approximately 125°C, sulfolene decomposes to butadiene and SO2. This simple method could be used to separate butadiene from a mixture of C4 olefins because the olefins do not react with SO2. 

By a sequence of thermal and photochemical steps in the course of a simple sulfolene reaction, stereospecific isomerizations are possible429-431 (equation 71). On the other... 

A direct insertion of sulfur dioxide into a C—C bond has been observed under photochemical conditions 3 (equation 72) a related CH insertion followed by an intramolecular sulfinate to carbonyl addition yields the same system 3 (equation 73). A further sulfolene synthesis utilizes a three-component reaction see equation 74 (cf. Section IV below) 35. 

Another way to reduce the nucleophilicity of the sulfur atom is oxidation to the corresponding sulfones, sulfonamides or sultones. Thus, diallyl sulfone undergoes RCM to the corresponding sulfolene smoothly in the presence of... 

Ethylene disulfonyl-1,3-butadiene (43) is an example of an outer-ring diene with a non-aromatic six-membered heterocyclic ring containing sulfur. It is prepared by thermolysis of sulfolenes in the presence of a basic catalyst. It is very reactive [43] and even though it is electron-deficient, it readily reacted with both electron-rich and electron-poor dienophiles (Equation 2.15). 

Ando K., Takayama H. Heteroaromatic-Fnsed 3-Sulfolenes Heterocycles 1994 37 1417-1439... 

The Diels-Alder reaction is usually reversible and has been used to protect double bonds. A convenient substitute for butadiene in the Diels-Alder reaction is the compound 3-sulfolene since the latter is a solid that is easy to handle while the former is gas. " Butadiene is generated in situ by a reverse Diels-Alder reaction (see 17-20). 

The most synthetically useful cheletropic elimination involves 2,5-dihydrothiophene-1,1-dioxides (sulfolene dioxides). At moderate temperatures they fragment to give dienes and sulfur dioxide.301 The reaction is stereospecific. For example, the dimethyl derivatives 22 and 23 give the E,E- and Z,E-isomers of 2,4-hexadiene, respectively, at temperatures of 100°-150°C.302 This stereospecificity corresponds to disrotatory elimination. 

Sulfolene dioxide is subject to a-lithiation and alkylation, and this reaction has been used to introduce the ring into more complex molecules. 

Sulfolene dioxide thermolysis has also been applied to formation of o-quinodimethanes. 

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