98289-60-2Relevant academic research and scientific papers
Novel ipso-Substitution of p-Sulfinylphenols through the Pummerer-Type Reaction: A Selective and Efficient Synthesis of p-Quinones and Protected p-Dihydroquinones
Akai, Shuji,Takeda, Yoshifumi,Iio, Kiyosei,Takahashi, Kenji,Fukuda, Nobuhisa,Kita, Yasuyuki
, p. 5526 - 5536 (2007/10/03)
The treatment of p-sulfmylphenols 3a-q with trifluoroacetic anhydride caused a Pummerer-type reaction on aromatic rings and concomitant desulfurization to give mixtures of the corresponding p-dihydroquinones 9 and p-quinones 10, which were subsequently oxidized under mild conditions to provide high yields of p-quinones 10. On the other hand, the treatment of p-(phenylsulfinyl)-phenyl ethers 6 with trifluoroacetic anhydride in the presence of styrene caused the direct ipso-substitution of the sulfinyl groups into trifluoroacetoxy groups, giving the protected dihydroquinones 14 in high yields. Both types of reactions were generally completed below room temperature within 1 h and compatible with various functional groups such as the allyl, carbonyl, ester, amide, and silyloxy groups. The preparation of the p-sulfmylphenols 3 and the silyl ethers 6 is also described through p-specific thiocyanation of phenols followed by the Grignard reaction and oxidation.
Additions to Alkenes via Metal Ion-Promoted Oxidation of Dialkyl and Diaryl Disulphides
Bewick, Alan,Mellor, John M.,Owton, W. Martin
, p. 1039 - 1044 (2007/10/02)
Reactions of alkenes with di-n-propyl, diphenyl, and dibenzyl disulphide in the presence of lead(IV) salts in trifluoroacetic acid-dichloromethane are described.The products, vicinal trifluoroacetoxysulphides, are obtained in higher yields with manganese(III) salts as the oxidant.Alternative reaction conditions with use of iron(III) salts or in the absence of added metal salts are also described.Trifluoroacetoxysulphides derived from diphenyl disulphide react with acetonitrile under Ritter conditions to give acetamidosulphides but trifluoroacetoxysulphides derived from dibenzyl disulphide only give the vicinal acetamidosulphides in poor yield as a result of an alternative reaction pathway affording benzylacetamide.Conversions of acetamidosulphides into aminosulphides and into acetamidothiols are described.
