Methyl styryl sulfone

A useful method of utilizing vinyl sulfones (specifically methyl styryl sulfones) for the preparation of thiane dioxides in good yields is illustrated in equation 125333. 

Thus, the dianion derived from a-amino acid substitutes the /1-chloride to give the ester of 2-(phenylsulfonyl)ethenyl amino acid and subsequent desulfonylation provides N-(benzoyl)vinylalanine methyl ester (62) (equation 61). The conjugate addition of enolates to methyl styryl sulfone (63) and subsequent intramolecular addition to the carbonyl moiety provide a synthetically valuable method for the construction of bicyclic and tricyclic skeletons52. Desulfonylation of the cyclization product 64 with sodium in ethanol-THF gives the diene 65 in good yield (equation 62). 

Takaki reports that ketone enolates add to dimethylstyryl sulfonium perchlorate (155) or methyl styryl sulfone (156) in a Robinson-type annulation sequence to afford the corresponding 3-hydroxythiadecalin (157) or 5-dioxide (158), respectively subsequent reductive desulfonation of (158) affords diene (159).131 However, additions to acceptor (155) suffer from competing cyclopropanation which is dependent on the electrophilicity of the carbonyl group and the ring size of the ketone (Scheme 61). As an aside, DeLucchi reports that l,l-bis(benzenesulfonyl)ethylene (160) adds to ketones at the more substituted a-carbon under neutral conditions in refluxing acetonitrile (equation 18).132... 

Certain substituted sulfones may be obtained by special methods for instance, vinyl sulfones (82) may be formed by addition of a sulfonyl carbanion (83) to a carbonyl compound followed by elimination (Scheme 34). An example when X = H is the synthesis of methyl styryl sulfones (84) by the Knoevenagel condensation of an aromatic aldehyde with a methanesulfonylacetate (85) followed by dealkylation-decarboxylation of the intermediate product by treatment with lithium iodide in DMF (Scheme 35). 

S-Dioxide [15436-11-0]. [2- Methylsulfonyl)ethenyl benzene, 9CI. P- Methylsulfonyl)styrene. Methyl styryl sulfone. 1- Methylsulfonyl)-2-phenylethylene C9H10O2S M 182.243 Solid. Mp 76-78°. 

Transprotonation equilibrium plays a vital role in the Michael addition of enolates to methyl-styryl sulfone 536. The primary anion obtained this way cyclizes to the anellation product 538 in quantitative yield. 

Methyl styryl ketone. See Benzylidene acetone Methyl succinate. See Dimethyl succinate Methylsufone. See Dimethyl sulfone 5-Methyl-3-sulfanilamidoisoxazole. See Sulfamethoxazole... 

Ci4Hi402S, Dibenzyl sulfone c15h14o2s, cis-Styryl p-tolyl sulfone [(Z)-1 -Methyl-4-(2-phenylethenyl)sulfonylbenzene] c15HI4o2s, frans-Styryl p-tolyl sulfone [( )-l-Methyl-4-(2-phenylethenyl)sulfonylbenzene] C12H10O4S2, Diphenyl disulfone... 

Wegener and coworkers63 have reported the detailed investigation of a series of styryl methyl sulfones. 

Z)-1 -Methyl-4-(2-phenylethenyl)sulfonylbenzene] C,5Hi402S, trans-Styryl p-tolyl sulfone... 

A-Alkylpyridinium salts 20 with alkyl chains from 14 to 22 carbon atoms andp substituents such as methyl, phenyl, and styryl groups (stilbazolium salts) with Cl", Br", I", BPh ", and C H SOj" counteranions were prepared by Ster et al. [27]. The stability of the SmA phase increased with the size of the anion, but no mesophase was observed with heptyl sulfonate. 

Once deprotonated by a strong base, the carbanion will react with electrophilic carbon in an alkyl halide or sulfonate ester to elongate the side-chain alkyl group, or with carbonyl carbon in an aldol or Claisen type reaction. The aldol readily loses water to form an alkenyl derivative, where the double bond is conjugated with the pyrimidine ring. Selective reactivity is demonstrated by the reaction of 2,5-dimethylpyrimidine with benzaldehyde, where only the electrophilic 2-methyl group reacts, to yield the 2-styryl derivative (389) (Scheme 64). Several examples are known . 

The PE spectrum of styryl methyl sulfone measured by Cauletti and coworkers59 is of similar complexity with its first and second bands assigned to ring n orbitals, namely 7t =9.08eV and 72 = 9.66eV (n2,a2). Colonna and coworkers60 also measured... 

The milder conditions needed for the sulfonation of the styryl derivative 160 as compared with 2-phenylbenzoxazole 158 are a reflection of the activating effect of the alkenic double bond. 2-Methyl-4,5-diphenyloxazole 162 with a large excess of chlorosulfonic acid (13 equivalents) at 85 °C for 13 hours afforded the 4, 4"-disulfonyl chloride 163 (Equation 43). The / ara-sulfonation was shown by NMR spectral analysis of the bis-7V 7V -dimethylsulfonamide derivative 164 (Equation 43). 

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