Intramolecular hydrogen abstraction reaction in carbohydrate chemistry. Synthesis of chiral 2,7-dioxabicyclo[2.2.1]heptane and 6,8-dioxabicyclo[3.2.1]octane ring systems
作者:Cosme G Francisco*、Antonio J Herrera、Ernesto Suárez
DOI:10.1016/s0040-4039(00)01393-9
日期:2000.10
of specifically protected alditols with (diacetoxyiodo)benzene or iodosylbenzene and iodine is a mild and selective procedure for the synthesis of chiral 6,8-dioxabicyclo[3.2.1]octane and 2,7-dioxabicyclo[2.2.1]heptane ringsystems under neutral conditions. This methodology can be useful not only for the preparation of chiral synthons but also for the selective oxidation of specific carbons of the carbohydrate
Intramolecular Hydrogen Abstraction Reaction Promoted by Alkoxy Radicals in Carbohydrates. Synthesis of Chiral 2,7-Dioxabicyclo[2.2.1]heptane and 6,8-Dioxabicyclo[3.2.1]octane Ring Systems
作者:Cosme G. Francisco、Antonio J. Herrera、Ernesto Suárez
DOI:10.1021/jo026004z
日期:2002.10.1
for the synthesis of chiral 6,8-dioxabicyclo[3.2.1]octane and 2,7-dioxabicyclo[2.2.1]heptane ring systems under neutral conditions. This reaction can be considered to be an intramolecular glycosidation that goes through an intramolecular hydrogen abstraction promoted by an alkoxy radical followed by oxidation of the transient C-radical intermediate to an oxycarbenium ion. This methodology is useful