112449-89-5Relevant academic research and scientific papers
Additions of nucleophiles to 3-oxo-2,3-dihydrothiophene 1,1-dioxides. Formation of vinyl sulfides, thioacetals and enaminones
Hofslokkcn, Nini Unn,Skattebol, Lars
, p. 3085 - 3088 (2007/10/03)
3-Oxo-2,3-dihydrothiophene 1,1-dioxide (la) was prepared by oxidation of the commercially available 3methoxythiophene with dimethyldioxirane. Some other substituted 3-methoxythiophene derivatives were oxidized as well. Although the yields of these reactio
Michael additions to 3(2H)-thiophenone 1,1-dioxide
Hofslokken, Nini,Flock, Solveig,Skattebo, Lars
, p. 119 - 122 (2007/10/02)
The addition of thiols and amines to 3(2H)thiophenone 1,1-dioxide takes place with extrusion of sulfur dioxide, furnishing in high yields the corresponding vinyl sulfides and enamines. Addition of dithiols afforded the corresponding thioacetals. The rates of the Michael addition and the extrusion reaction are strongly influenced by the solvent employed. In ethanol, sulfur dioxide extrusion took place even at room temperature.
Biotransformation of αβ-unsaturated carbonyl compounds: sulfides, sulfoxides, sulfones, nitriles and esters by yeast species: carbonyl group and carbon-carbon double bond reduction
Koul, Surinder,Crout, David H. G.,Errington, William,Tax, Jiri
, p. 2969 - 2988 (2007/10/03)
The reduction of αβ-unsaturated ketones with γ-sulfide, sulfoxide, sulfone, nitrile and ester functions has been investigated.Both C=O and C=C reduction was observed.In the sulfur series, C=O bond reduction was always observed, but significant C=C bond reduction was observed only with the sulfide.The unsaturated nitriles gave the corresponding alcohols as the major bioreduction product, with smaller but significant amounts of fully reduced product.A similar result was obtained with the ester substrate.Relative and absolute configurations of bioreduction products were determined.A comparison was made between reductions catalysed by bakers' yeast (Saccharomyces cerevisiae) and by other yeasts (Zygosaccharomyces rouxii, Pichia capsulata, P. farinosa, Candida chalmersi and C. diddensiae).The tendency of Z. rouxii to give products enantiomeric with thouse obtained using S. cerevisiae was noted.The relationship between substrate structure and the stereochemistry of C=C double bond reduction is discussed.
Synthesis of a 4-Acylcyclohexa-2,5-dienone: 3,4-Dihydro-3,3,8a-trimethylnaphtalene-1,6(2H,8aH)-dione
Waring, Anthony John,Zaidi, Javid Hussain
, p. 631 - 640 (2007/10/02)
The synthesis is reported of 3,4-dihydro-3,3,8a-trimethylnaphtalene-1,6-(2H,8aH)-dione (11; R = Me).This is the first isolated 4-acylcyclohexa-2,5-dienone, a class of compounds postulated particularly as intermediates in the Fries and photo-Fries rearrangements.The dienone undergoes very easy acyl cleavage in the presence of bases or dilute acids, to form a phenolic acid (18).Similar cleavage, or a retro-Fries migration of the acyl group from the 4-position to the dienone ring oxygen, has prevented isolation of 4-acetyl-4-methylcyclohexa-2,5-dienone.Concentrated aqueous sulphuric acid causes rearrangement of the dienone to 3,4-dihydro-8-hydroxy-3,3,5-trimethylnaphtalen-1(2H)-one (13; R = Me), via recyclisation of 18.In trifluoroacetic acid solutions the same product (13, R = Me) is formed from the dienone by direct, formal dienone-phenol rearrangement.
