- (Diphenoxyphosphoryl)methyl p -tolyl sulfoxide: A new reagent for Z -selective synthesis of racemic and optically active vinyl sulfoxides
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Racemic and optically active (+)-(S)-(diphenoxyphosphoryl)methyl p-tolyl sulfoxide were prepared and used as Horner olefination reagents. Their reaction with aromatic and aliphatic aldehydes afforded the corresponding racemic and enantiomeric α,β-unsatura
- Midura, Wanda H.,Ewas, Ashraf M. Mohamed,Miko?ajczyk, Marian
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p. 535 - 540
(2016/04/05)
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- Asymmetric claisen rearrangements on chiral vinyl sulfoxides
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Highly diastereoselective Claisen rearrangements of acyclic allyl vinyl ethers bearing a chiral sulfoxide at C-5 provide γ-δ-unsaturated aldehydes or ketones with up to two consecutive asymmetric centers in the molecule whilst preserving a useful vinyl su
- De La Pradilla, Roberto Fernandez,Montero, Carlos,Tortosa, Mariola,Viso, Alma
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supporting information; experimental part
p. 697 - 709
(2009/07/25)
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- Additive Pummerer reactions of vinylic sulfoxides. Synthesis of γ-hydroxy-α,β-unsaturated esters, α-hydroxyketones, and 2-phenylsulfenyl aldehydes and primary alcohols
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Treatment of β-monosubstituted vinylic sulfoxides 1 with trifluoroacetic anhydride in dichloromethane gave excellent yields of 1,2-bis(trifluoroacetoxy)thioethers 6. Mildly basic methanolysis of 2-alkyl-substituted 6 gave α-hydroxyaldehydes 11 as monomer-dimer mixtures; similar treatment of the 2-aryl analogues afforded aryl (hydroxymethyl) ketones 12. Compounds 11 underwent Wittig reactions with methoxycarbonylmethylenetriphenylphosphorane to give high yields of γ-hydroxy-α,β-unsaturated esters 13, predominantly as the E-isomers. β-Monosubstituted vinylic sulfoxides 1 possessing a β-aryl group, and β-disubstituted vinylic sulfoxides 3 reacted with trifluoromethanesulfonic anhydride-sodium acetate in acetic anhydride to give 2-(phenylsulfenyl) acylals 14. These gave 2-phenylsulfenyl aldehydes 15 upon basic methanolysis, and the corresponding primary alcohols 16 on reduction with sodium borohydride. Reaction of both geometric isomers of enantiomerically pure vinylic sulfoxide 1o with TFAA gave racemic 6o as a mixture of diastereomers. Reaction of optically pure (E)- and (Z)-1p with trifluoromethanesulfonic anhydride-sodium acetate in acetic anhydride gave acylal 19 in 10.5 and 23% e.e., respectively.
- Craig, Donald,Daniels, Kevin,MacKenzie, A. Roderick
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p. 11263 - 11304
(2007/10/02)
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