title: Cyclodextrins containing an acetone bridge. Synthesis and study as epoxidation catalysts.
abstract: Three cyclodextrine derivatives (6A,6D-di-O-(prop-2-one-1,3-dienyl)-alpha-cyclodextrin (1), 6-O-(prop-2-one-1-yl)-alpha-cyclodextrin (2) and 6A,6D-di-O-(prop-2-one-1,3-dienyl)-beta-cyclodextrin (3)) were synthesised and investigated as epoxidation catalysts. The three compounds were synthesised from the corresponding perbenzylated cyclodextrins which were mono- or didebenzylated in the 6-position using Sinaÿ's method. Reaction with NaH and methallyl chloride in the case of 2, or methallyl dichloride in the case of 1 and 3, followed by dihydroxylation, periodate cleavage and protection group removal gave the target compounds. All three compounds catalysed, in the presence of oxone, the epoxidation of a series of alkenes. Epoxidation was compared to the reaction catalysed by simple ketones and inhibition was studied.
authors.affiliation: Department of Chemistry, University of Aarhus, Langelandsgade 140, DK-8000, Aarhus, Denmark.
authors.forename: Cyril
authors.initials: C
authors.lastname: Rousseau
authors.forename: Brian
authors.initials: B
authors.lastname: Christensen
authors.forename: Torben Ellebaek
authors.initials: TE
authors.lastname: Petersen
authors.forename: Mikael
authors.initials: M
authors.lastname: Bols