Pectenotoxin-2 Synthetic Studies. 1. Alkoxide Precoordination to [Rh(NBD)(DIPHOS-4)]BF4 Allows Directed Hydrogenation of a 2,3-Dihydrofuran-3-ol without Competing Furan Production
摘要:
[GRAPHICS]The alkoxide-directed hydrogenation shown is reported as a key step in a concise synthesis of a fully functionalized precursor to the C29-C40 FIG sector of pectenotoxin-2.
Decarboxylative Isomerization of <i>N</i>-Acyl-2-oxazolidinones to 2-Oxazolines
作者:Aaron E. May、Patrick H. Willoughby、Thomas R. Hoye
DOI:10.1021/jo800076f
日期:2008.4.1
N-Acyl-2-oxazolidinones are ring-opened by lithium iodide and decarboxylated in the presence of a mild proton source. Further reaction with an amine base provides 2-oxazolines. The transformation is general for oxazolidinones unsubstituted in the 5 position and occurs under mild conditions (25-50 degrees C). These results complement the existing methods for this transformation by allowing lower temperatures and/or avoiding metal catalysts.
Alkoxide precoordination to rhodium enables stereodirected catalytic hydrogenation of a dihydrofuranol precursor of the C29-40 F/G sector of pectenotoxin-2
作者:Xiaowen Peng、Dmitriy Bondar、Leo A. Paquette
DOI:10.1016/j.tet.2004.06.142
日期:2004.10
enantioselective synthesis of the stereochemically fully endowed C(29-40) fragment of pectenotoxin-2 is detailed. The highlight of the synthesis is an alkoxide-directed hydrogenation in which ionic complexation of the deprotonated substrate to [Rh(NBD)(DIPHOS-4)]BF4, accomplished by the co-addition of an equivalent of sodium hydride in THF, completely deters a kinetic tendency for dehydration and properly
Pectenotoxin-2 Synthetic Studies. 1. Alkoxide Precoordination to [Rh(NBD)(DIPHOS-4)]BF<sub>4</sub> Allows Directed Hydrogenation of a 2,3-Dihydrofuran-3-ol without Competing Furan Production
作者:Leo A. Paquette、Xiaowen Peng、Dmitriy Bondar
DOI:10.1021/ol010302l
日期:2002.3.1
[GRAPHICS]The alkoxide-directed hydrogenation shown is reported as a key step in a concise synthesis of a fully functionalized precursor to the C29-C40 FIG sector of pectenotoxin-2.