Chromatography-Free Wittig Reactions Using a Bifunctional Polymeric Reagent
作者:Peter Shu-Wai Leung、Yan Teng、Patrick H. Toy
DOI:10.1021/ol1021614
日期:2010.11.5
The first example of a polystyrene bearing two distinct reagent groups has been prepared. This phosphine and amine functionalized material was used in one-pot Wittig reactions with an aldehyde and either an α-halo-ester, -ketone, or -amide. Due to the heterogeneous nature of the polymer, the desired alkene product of these reactions could be isolated in excellent yield in essentially pure form after
Rasta Resin-PPh3 and its Use in Chromatography-Free Wittig Reactions
作者:Patrick Toy、Peter Leung、Yan Teng
DOI:10.1055/s-0030-1258130
日期:2010.8
Rasta resin-PPh3 (RR-PPh3), a new heterogeneous polystyrene-based phosphine, has been synthesized and used in one-potWittig olefination reactions of aldehydes. In these reac- tions an excess of RR-PPh3 was used for the in situ generation of the phosphorane reactant, and allowed for isolation of a high yield of very pure alkene product after only filtration and solvent re- moval. The excellent results
Rasta 树脂-PPh3 (RR-PPh3) 是一种新型多相聚苯乙烯基膦,已被合成并用于醛的单锅 Wittig 烯化反应。在这些反应中,过量的 RR-PPh3 用于原位生成正膦反应物,并允许在仅过滤和去除溶剂后分离出高产率的非常纯的烯烃产物。本研究中获得的优异结果归因于 rasta 树脂结构的柔韧性,这使得它比以前用于在 Wittig 反应中支持膦试剂的其他异质聚苯乙烯材料更少依赖于溶胀。碳-碳双键构成有机化学中的中心官能团之一,合成这种键的重要方法是Wittig反应。这种转化涉及使用磷烷试剂将亚烷基转移到醛或酮基团,同时将原始羰基氧转移到磷(方案 1)。1 通常,正膦是通过叔膦(通常为 PPh3)与卤代烷反应制备的,然后用适当的碱对由此形成的鏻盐进行去质子化。