Trimethylsulfonium ion

The very rapid exchange reaction between dimethyl sulfide and MeSSMe2 (43) is accompanied by a much slower, and irreversible, reaction (47) between the same reagents that involves nucleophilic attack of the sulfide on one of the sulfonium methyl groups and that leads to the formation of trimethylsulfonium ion and dimethyl disulfide (Kim and Caserio, 1974). Other sulfides (RSCH3) react similarly to give RS(CH3)2. When the sulfide is trideuteriomethyl... 

Use Learning By Modeling to view the geometry of sulfur in trimethylsulfonium ion. 

It is only more recently that reactions of Charge type 4 have been known and studied, but the theory proposed by Hughes and Ingold predicted the results accurately here too, for the reaction of trimethylamine with trimethylsulfonium ion (Equation 4.12) proceeds more rapidly in nonpolar than in polar solvents.18... 

The second-order reaction between trimethylamine and the trimethylsulfonium ion gives the predicted rate decrease with increasing solvent polarity [69] cf. reaction type (e) in Table 5-4. 

Finally, as an example of reaction type (f) in Table 5-4, the alkaline hydrolysis of the trimethylsulfonium ion demonstrates the predicted large rate decrease by increasing the proportion of water in an aqueous ethanolic reaction medium [70],... 

Conversely, reactions in which ionic reagents lead to neutral products are retarded by solvents and take place more slowly, the more polar is the solvent for the energy of solvation of the transition state will be less than that of the reactants since it is part way to the products and so the charges in it are smaller. A good example is the reaction of trimethylsulfonium ion with ethoxide ion,... 

Sulfur ( S)(I= 3j2). S NMR chemical shifts were calculated by the scaled DFT and EMPI approaches for the fluoride, chloride and bromide of trimethylsulfonium ion and S-methyltetrahydrothiophenium ion, in addition to the free cations. and S NMR chemical shifts of sulfur dioxide (SO2) were measured for the range of density (0.05-0.3 mol L ) in the gas phase at 300 and 333 K The chemical shifts for both nuclei are linearly dependent on density showing an increase of magnetic shielding and a decrease of S shielding due to intermolecular interactions. ... 

The simplest synthesis of 5-methyltetrahydrofolic acid is from tetrahydrofolic acid (FH4) and trimethylsulfonium ion, a reaction carried out by microorganisms in the soil. 

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