Sulfides sulfoxide synthesis

Figure 11.5 Structure and synthesis of the polyoxometalate (POMs) library L4 and POM-catalyzed sulfide-sulfoxide oxidation of 11.4.

In this chtqjter oxidation of an activated C—bond adjacent to a sulfur atom refers to any process whereby a C—bond at the a-position of an alkyl sulfide is replaced by a C—bond, where X is a halogen atom or an oxygen-, nitrogen-, carbon-, or sulfiir-based substituent (equation 1). Processes in which a stabilized anion is generated adjacent to the sulfur atom of a sulfide, sulfoxide or sulfone and subsequently used as a nucleophile in addition or substitution reactions are excluded from this section. The use of such anions in organic synthesis is dealt with in Volume 1, Chapter 2.3. 

Synthesis of Methyl Sulfide, Sulfoxide and Sulfone Metabolites of... 

Table IX. Synthesis of methyl sulfide, sulfoxide and sulfone...

A platform had been created from which it was felt that the enantioselective sulfoxide synthesis could be developed into a process that would match logistical as well as quality requirements. However, it is important to stress that other variations of the titanium-catalyzed approach had been concomitantly identified but the decision was taken to focus solely on the present option. One of the most important and challenging aspects in this regard was to demonstrate how the oxidation step could be fitted into the existing manufacture of the prochiral sulfide (pyrmetazole) and, if not, what changes or modifications would be needed. This... 

Russell s studies of vinylation reactions using vinylstannanes also examined similar reactions of vinyl sulfides, sulfoxides and sulfones [43a]. For example, isopropyl radical, generated from isopropyl mercuric chloride, adds to the non-sulfur-substituted alkene carbon of compounds 96, 97 and 98 to form the vinylated product 99 (Scheme 19). Recently, Caddick applied an intramolecular version of this process using alkyl halides and sulfides or sulfoxides in the presence of tributyltin hydride to the synthesis of indole derivatives [57]. 

Oxidation of sulfides. The synthesis of chiral sulfoxides by oxidation of sulfides has... 

Methods available for the synthesis of thiophene derivatives in which the ring carbon atom is linked to a sulfur have been reviewed <86HC(44/3)135>. The compounds covered include thio-phenethiols, sulfides, sulfoxides, sulfones, sulfonic acid derivatives, thiocyanatothiophenes, etc. A brief account of the reactions of thiophenes with electrophilic sulfur had also been presented in CHEC-I <84CHEC-I(4)74i>. Therefore only those few reports which have appeared subsequent to the above will be discussed here. 

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