New strategy to construct fused/bridged/spiro carbocyclic scaffolds based on the design of novel 6-C synthon precursor
作者:Jia Liu、Xi Wang、Chang-Liang Sun、Bi-Jie Li、Zhang-Jie shi、Min Wang
DOI:10.1039/c0ob00660b
日期:——
In this article we report a new strategy to build fused/spiro/bridged carbocyclic systems with a novel 6-C synthon from readily available diallyl diacetates through the sequential Pd-catalyzed double allyl alkylation and Diels–Alder annulation. Further exploration on the application of this strategy can construct useful complex scaffolds.
Rhodium- and palladium-catalysed formation of conjugated mono- and bis-exocyclic dienes. 5-Exo-trig versus 6-endo-trig cyclisations
作者:Ronald Grigg、Paul Stevenson、Tanachat Worakun
DOI:10.1039/c39840001073
日期:——
2-Bromo-1,6-dienes are catalytically cylised to give conjugated 5-membered bis-exocylic dines and 6-membered mono-exocyclic dienes by rhodium and palladium catalysts, the specificity for a 5- or 6-membered ring being a function of substrate, catalyst, and added base; 2-bromo-1,7-dienes cyclise regiospecifically to give 6-membered rings.
2-Cyclopentenone derivatives have been efficiently synthesized from 5-bromo-5-hexen-2-ones via palladium-catalyzedintramolecular carbonyl α-alkenylation followed by double-bond migration under mild reaction conditions.