1-Naphthylpropargyl ether group: A readily cleaved and sterically minimal protecting system for stereoselective glycosylation
(Chemical Equation Presented) The (1-naphthyl)propargyl group is introduced as a sterically unobtrusive alcohol protecting group that is cleaved in a single step by exposure to dichlorodicyanoquinone in wet dichloromethane. In conjunction with the 4,6-O-b
Crich, David,Wu, Baolin
p. 4879 - 4882
(2007/10/03)
Chiral ruthenium-catalyzed hydrogenation of β-keto sulfoxides
The diastereoselective catalytic hydrogenation of β-keto sulfoxides in the presence of ruthenium complexes was studied. Optically pure β-keto sulfoxides were hydrogenated in the presence of achiral catalysts leading to moderate yields and stereoselectivities. Using chiral ruthenium catalysts such as [(R)-MeO-BIPHEPRuBr2] and [(S)-MeO-BIPHEPRuBr2], the hydrogenation proceeded in good yields with very high diastereoselectivity. Chirality at the secondary centre of the β-hydroxy sulfoxides produced was controlled by the catalysts.
De Paule, Sebastien Duprat,Piombo, Laurent,Ratovelomanana-Vidal, Virginie,Greek, Christine,Genet, Jean-Pierre
p. 1535 - 1537
(2007/10/03)
The preparation of β-hydroxysulfoxides
Oxidation of β-hydroxy thioethers with MnO2-aqu.35%/HCl in methanol gives β-hydroxy sulfoxides in high yields.
Gabbi, Cristina,Ghelfi, Franco,Grandi, Romano
p. 2857 - 2863
(2007/10/03)
Stereoselective Synthesis of Alcohols, I Synthesis of One-Carbon Homologous Allyl Alcohols from Aldehydes or Ketones
The high yield conversion of aldehydes and ketones 2 to the one-carbon homologous allyl alcohols 3 is achieved by condensation to the vinyl sulfoxides 7, isomerisation to the allyl sulfoxides 9, and subsequent sigmatropic rearrangement.