K. Bedjeguelal et al., Intramolecular Heck cyclisation-beta-alkoxy elimination in carbohydrate chemistry. A simple route to to enantiopure annelated dioxatricyclic compounds, SYNLETT, (6), 1999, pp. 762-764
Enantiopure cis-fused pyrano[2,3c]pyrans are obtained from glycals via an i
ntramolecular Heck cyclization followed by a palladium-beta-alkoxy eliminat
ion.