Intramolecular palladium-catalysed cross coupling; a direct route to γ-Oxo-α,β-unsaturated macrocycles.
摘要:
Intramolecular Pd0-catalysed cross coupling of structures terminating in an acyl chloride and a beta-stannylalkenoate has provided a new and an efficient route to 10-20 membered gamma-oxo-alpha,beta-unsaturated macrolides. Both the Z- and E- beta-stannylalkenoates afforded identical macrocylic products demonstrating that under the reaction conditions thermodynamic equilibration of the first formed cross coupled product was most probably occurring. The method has been used to synthesise the macrocyclic framework of the antibiotic A26771B and norpatulolide B.
Intramolecular palladium-catalysed cross coupling; a route to γ-oxo-α,β-unsaturated macrocycles
作者:Jack E. Baldwin、Robert M. Adlington、Steve H. Ramcharitar
DOI:10.1039/c39910000940
日期:——
A new and relatively simple method involving Pd0-catalysed cross coupling of acid chlorides and β-stannyl alkenoates provides an efficient route to γ-oxo-α,β-unsaturated macrolides.
Ring Expansions of β-Keto Lactones with Zinc Carbenoids: Syntheses of (+)-Patulolide A and (±)-Patulolide B
作者:Matthew D. Ronsheim、Charles K. Zercher
DOI:10.1021/jo0264776
日期:2003.3.1
A one-pot ringexpansion/oxidation/elimination method has been developed in which beta-keto lactones are converted efficiently to alpha,beta-unsaturated-gamma-keto lactones. The reaction can be successfully applied to a variety of ring sizes. Alkene stereochemistry is dependent upon ring size and reaction conditions. The method was applied to the synthesis of (+)-patulolide A.