623560-29-2Relevant academic research and scientific papers
Condition-directable reaction: Regio- and stereoselective elimination of 2,3-dibromo-2-methylpropyl phenyl sulfone via base-solvent selection
Li, Xiaojin
, p. 393 - 399 (2006)
Diversity-oriented organic synthesis is an important approach for combinatorial chemistry and drug discovery. An example of this approach is selective elimination of 2,3-dibromo-2-methylpropyl phenyl sulfone 5 to potentially useful vinyl sulfones 6E/Z and
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.
γ-allyl Phosphinoyl Phenyl Sulfone (GAPPS): A Conjunctive Reagent for the Synthesis of EE, EZ, and ET 1,3-Dienes
Li, Xiaojin,Lantrip, Douglas,Fuchs, Philip L.
, p. 14262 - 14263 (2007/10/03)
A three-operation conjunctive strategy is available for the synthesis of EE, EZ, and ET dienes. This protocol employs a sequential Wadsworth?Emmons reaction using a GAPPS reagent followed by alkylation of an allylic sulfone anion, and finally ligand-mediated, palladium-catalyzed desulfonylation. Copyright
