74963-80-7Relevant academic research and scientific papers
Isomerisation of Vinyl Sulfones for the Stereoselective Synthesis of Vinyl Azides
Collins, Niall,Connon, Robert,Evans, Paul,Sánchez-Sanz, Goar
supporting information, p. 6228 - 6235 (2020/10/02)
Reported is the construction, and facile base-mediated conversation of ten differently substituted 3-azido E-vinyl sulfones (γ-azido-α,β-unsaturated sulfones) into their isomeric vinyl azide counterparts. The requisite 3-azido E-vinyl sulfones were prepared from 3-bromo E-vinyl sulfones, which in turn were accessed from allyl sulfones via a bromination-elimination sequence. In relation to this a one-pot azidation-isomerisation sequence was developed which enabled the direct formation of the vinyl azides from the corresponding 3-bromo E-vinyl sulfones. Similarly, a convenient one-pot Horner–Wadsworth–Emmons olefination-isomerisation approach was utilised in order to prepare some of the allylic sulfones used in this study. The vinyl azide forming process typically proceeded with high levels of Z-selectivity, although this was dependent on the vinyl sulfone substitution pattern. Thus, with either no substituent or a methyl group in the γ- or β-position, relative to the sulfone, good, to high levels of Z-selectivity (Z/E = 85:15 to ≥ 95:5) were obtained. However, incorporation of an α-sulfonyl methyl substituent led to an E-selective process (Z/E = 20:80). A non-bonding interaction between the azido group and the α-sulfonyl vinylic proton is proposed, which acts as a conformational control mechanism to help guide the stereochemical outcome.
A method for the conversion of sulfoximines to sulfones: Application to polymer-bound sulfoximines and to the synthesis of chiral sulfones
Hachtel, Jochen,Gais, Hans-Joachim
, p. 1457 - 1465 (2007/10/03)
Reaction of N-alkyl, N-aryl, and N-H sulfoximines with m- chloroperbenzoic acid cleanly gives the corresponding sulfones in high yield. In the case of the cleavage of N-alkyl and N-arylsulfoximines, formation of the corresponding nitroso compounds as the other reaction product was proven. Starting from enantio- and diastereopure sulfoximines, a number of chiral sulfones, including the axially chiral sulfone 6 and the sulfonyl- functionalized homoallylic alcohol 8, have been prepared. Reaction of the enantiopure sulfoximine 30 with Merrifield resin gave the polymer-bound sulfoximine 32. Oxidative cleavage of 32 afforded the sulfone 16 in high yield. Deprotonation of the sulfoximine resin 32 and reaction of Li-32 with benzaldehyde and propanal furnished the β-hydroxysulfoximine resins 33a and 33b, respectively. Oxidative cleavage of 33a and 33b readily afforded the β- hydroxy sulfones 14a and 14b, respectively.
Stereoselective preparation of vinyl sulfones by protodesilylation of allyl silanes
Funk, Raymond L.,Umstead-Daggett, Joy,Brummond, Kay M.
, p. 2867 - 2870 (2007/10/02)
Allyl sulfones can be conjugated to furnish vinyl sulfones via allyl silane intermediates. The stereoselectivity observed in the protodesilylation step provides a new method for stereoselective preparation of (E)-di-and tri substituted vinyl sulfones.
Electrochemical oxidation of carboxylic acid anions in the presence of some mono- and di-subsituted olefins
Champagne, Philippe J.,Renaud, Roger N.
, p. 1101 - 1105 (2007/10/02)
The anodic oxidation of the sodium salts of acetic, propionic, and isovaleric acids was performed in the presence of a series of ethylenic compounds bearing electron-withdrawing substituents.The results showed that under certain experimental conditions the electrogenerated radicals added to the ethylenic double bond to give mainly 1,2-dialkylated products.The stereoisomers obtained were separated and whenever possible, identified.Their physical properties are reported.
