title: Reductive opening of carbohydrate phenylsulfonylethylidene (PSE) acetals.
abstract: The phenylsulfonylethylidene (PSE) acetal is a relatively new protecting group in carbohydrate chemistry. However, carbohydrate-derived phenylsulfonylethylidene (PSE) acetals show a different behavior in reductive desulfonylation than simple symmetrical acetals. Here we have investigated various SET-type reaction conditions in order to open PSE acetals regioselectively and to produce chiral ω-hydroxyethenyl ethers. Whereas sodium amalgam leads to a mixture of regioisomeric vinyl ethers besides the ethylidene acetal, samarium iodide is suited for regioselective ring opening. This is shown with seven different carbohydrate PSE acetals, both of the 1,3-dioxane and the 1,3-dioxolane type.
authors.affiliation: Université d'Orléans et CNRS, ICOA, UMR 7311, BP 6759, F-45067 Orléans, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Chéry
authors.affiliation: Université d'Orléans et CNRS, ICOA, UMR 7311, BP 6759, F-45067 Orléans, France; Dipartimento di Chimica, Università Ca'Foscari di Venezia, Dorsoduro 2137, I-30123 Venezia, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Cabianca
authors.affiliation: Université d'Orléans et CNRS, ICOA, UMR 7311, BP 6759, F-45067 Orléans, France.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Tatibouët
authors.affiliation: Dipartimento di Chimica, Università Ca'Foscari di Venezia, Dorsoduro 2137, I-30123 Venezia, Italy.
authors.forename: Ottorino
authors.initials: O
authors.lastname: De Lucchi
authors.affiliation: Otto Diels Institute of Organic Chemistry, Christiana Albertina University of Kiel, Otto-Hahn-Platz 3/4, D-24118 Kiel, Germany.
authors.forename: Thisbe K
authors.initials: TK
authors.lastname: Lindhorst
authors.affiliation: Université d'Orléans et CNRS, ICOA, UMR 7311, BP 6759, F-45067 Orléans, France. Electronic address: patrick.rollin@univ-orleans.fr.
authors.forename: Patrick
authors.initials: P
authors.lastname: Rollin
mesh_terms: D000080:Acetals / Q000138:chemical synthesis*; D001597:Benzylidene Compounds / Q000737:chemistry*; D004146:Dioxanes / Q000737:chemistry; D004148:Dioxolanes / Q000737:chemistry; D007454:Iodides / Q000737:chemistry; D015394:Molecular Structure; D010084:Oxidation-Reduction; D012493:Samarium / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000080:Acetals; D001597:Benzylidene Compounds; D004146:Dioxanes; D004148:Dioxolanes; D007454:Iodides; D012493:Samarium; C025223:1,4-dioxane; C409809:samarium diiodide; C010962:formal glycol
keywords: Carbohydrate protecting groups; Phenylsulfonylethylidene (PSE) acetals; Reductive desulfonylation; SET; Sulfones; Vinyl ethers