Sulfide, dimethyl reaction with alkyl halides

Silver salts are also utilized to perform nucleophilic additions to disulfide bonds to yield sulfenamides (146). If alkyl halides are treated with stoichiometric AgBF4 in dimethyl sulfoxide solvent (DMSO, solvent), the corresponding aldehydes/ ketones will form in good yields. This reaction is an alternative to the well-known Swern oxidation (147). In addition, silver can drive the formation of dialkylper-oxonium ions from alkyl halides, which then oxidizes sulfoxides or sulfides (148,149). In the presence of AgN03, sulfides can be oxidized into a-chloro sulfoxides by SO2CI2 (Fig. 36) (150). 

Driven by the inability to substitute allyltin compounds at the 3-position, Keck examined intermolecular addition reactions of allyl sulfides [50]. He was able to show that 3-methyl- and 3,3-dimethyl-substituted allyl phenyl sulfides 86 and 88 undergo reaction with alkyl halides and alkyl phenyl selenides in the presence of hexabutylditin to form good yields of the allylation products (Scheme 18). These... 

When the [Fe(TPA)X2] catalysts are reacted with stoichiometric amounts of TBHP in the presence of alkanes, only the alkyl halide is formed and in good yield. 70-80 % of the TBHP oxidizing equivalents is converted into alkyl halide product. The absence of additional products greatly facilitates mechanistic interpretation of the results. For example, the band at 500 nm in [Fe(TPA)Br2] attributed to bromide-to-iron(III) charge transfer decays upon addition of TBHP concomitant with the appearance of the alkyl halide product. NMR studies of the reaction mixture show that the starting complex is converted to a (p-oxo)diferric species during the course of this reaction. Addition of dimethyl sulfide inhibits... 

S-Alkylatlon. Methyl iodide alkylates thioalkoxides and sulfides to produce sulfides and sulfonium ions, respectively. For example, thioalkoxides produced from thiocarbonyl compounds are methylated with methyl iodide to generate the corresponding methyl thioether (eq 22). Sulfonium halides, derived from the reaction of methyl iodide with an alkyl sulfide, are sometimes labile in solution and may undergo further reaction (eq 23). Dimethyl Sulfoxide when refluxed with an excess of methyl iodide produces trimethyloxosulfonium iodide, which is collected as a white solid and recrystallized from water. Similarly, methylation of Dimethyl Sulfide produces trimethylsulfonium iodide. Treatment of trimethyloxosulfonium and trimethylsulfonium salts... 

The reaction of thiols with alkyl halides produces sulfides, which are converted into sulfonium halides in the presence of excess alkyl halides.2680 Dimethyl sulfoxide (42) and acetic anhydride (41) react with starch365 to cause oxidation at the C-3 and C-6 positions, and methylthiomethyl ethers are formed at 0-6, according to the following reaction (43-46) ... 

Preparation of the lower dialkyl sulfides by the following general procedure has been described by McAllan and his co-workers 286 Sodium sulfide nonahydrate (1.5 moles) is dissolved in water (250 ml) in a three-necked flask fitted with a reflux condenser, dropping funnel, and stirrer, then the alkyl halide (2 moles) is added slowly with vigorous stirring. When the very exothermic reaction ceases, the mixture is heated under reflux for a further 3 h and the sulfide is distilled over in steam, separated, washed with water, 10% sodium hydroxide solution, and again water, dried over calcium chloride, and distilled. In this way were obtained dimethyl (b.p. 37.3°), diethyl (b.p. 92°),287 diisopropyl (b.p. 119.8°), dipropyl (b.p. 142.8°),288 and bis-(2-cyanovinyl) sulfide (m.p. 142-143°, from ethyl acetate-cyclohexane).289... 

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