Asymmetric synthesis of polyacetate derived building blocks with α-oxyanion functionality. Lewis acid catalyzed opening of 2,9-dioxabicyclo[3.3.1]nonan-3-ones
作者:Ralf Dunkel、H.M.R Hoffmann
DOI:10.1016/s0040-4020(99)00460-3
日期:1999.7
(Scheme 1) are obtainable from8-oxabicyclo[3.2.1]oct-6-en-3-one which functions as a meso-configurated 4-way optical switch. Lewis acid assisted nucleophilic ring opening of anomeric [3.3.1] oxabicyclic lactones is a key step. The utility of the methodology is exemplified by a 6 step synthesis of the C17–C23 fragment of spongistatin (altohyrtin) and C-glycoside analogues.