Regio- and Stereoselectivity of Water Elimination as a Function of Ring Size
作者:Björn Greve、Peter Imming
DOI:10.1021/jo970989g
日期:1997.11.1
The elimination of water from tertiary alcohols was studied for carbocycles of ringsize 5-16. The resulting olefins 3-5 were discriminated by NMR spectroscopy. The relative amount of their formation reflects the steric idiosyncrasies of the respective ring systems. The behavior of the medium-sized rings yielded experimental proof to the I-strain concept.
Bicyclic β-Hydroxytetrahydrofurans as Precursors of Medium Ring Keto-Lactones
作者:Helena M. C. Ferraz、Luiz S. Longo
DOI:10.1021/jo0626109
日期:2007.4.1
The reaction of a series of cis-fused bicyclic beta-hydroxytetrahydrofurans with ruthenium tetraoxide, generated in situ from ruthenium trichloride and sodium periodate, afforded 9- and 10-membered keto-lactones in moderate to good yields, in a clean and straightforward fashion. The starting beta-hydroxyethers were obtained from the corresponding 3-alkenols by two alternative procedures, depending on their pattern of substitution: (a) epoxidation by dimethyldioxirane, followed by base-catalyzed cyclization of the resulting epoxyalcohol, and (b) thallium trinitrate-mediated cyclization of the 3-alkenols, a method already described by our group.