Highly Functionalised Enantiopure 4-Hydroxypyridine Derivatives by a Versatile Three-Component Synthesis
作者:Christian Eidamshaus、Hans-Ulrich Reissig
DOI:10.1002/adsc.200800789
日期:2009.5
Abstractmagnified imageThe scope of a novel alkoxyallene‐based pyridine synthesis was expanded to enantiopure carboxylic acids and nitriles as starting materials. The enantiomeric purity of the chiral α‐secondary carboxylic acids and nitriles was completely preserved during this reaction sequence thus allowing the one‐pot preparation of a whole range of 4‐hydroxypyridines or their 4‐pyridinone tautomers in good yields.
A practical two-step procedure for the preparation of enantiopure pyridines: Multicomponent reactions of alkoxyallenes, nitriles and carboxylic acids followed by a cyclocondensation reaction
作者:Christian Eidamshaus、Roopender Kumar、Mrinal K Bera、Hans-Ulrich Reissig
DOI:10.3762/bjoc.7.108
日期:——
reaction of alkoxyallenes, nitriles and carboxylicacids to provide beta-methoxy-beta-ketoenamides which are transformed into 4-hydroxypyridines in a subsequent cyclocondensation. The process shows broad substrate scope and leads to differentially substituted enantiopure pyridines in good to moderate yields. The preparation of diverse substituted lactic acid derived pyrid-4-yl nonaflates is described