New and efficient conditions for the Z -selective synthesis of unsaturated esters by the Horner-Wadsworth-Emmons olefination
作者:François P Touchard
DOI:10.1016/j.tetlet.2004.05.026
日期:2004.7
The Horner-Wadsworth-Emmons reaction of both 1 (Still's reagent) and 2 (Ando's reagent) with aldehydes was studied. Tris[2-(2-methoxyethoxy)ethyl]amine (TDA-1) was shown to be an efficient additive when the reaction was performed in THF at −78 °C. Selectivities close to 95% were obtained in the condensation of 1 with aromatic aldehydes. The use of a 5-fold excess of 18C6 in this reaction had already
研究了1(Still试剂)和2(Ando试剂)与醛的Horner-Wadsworth-Emmons反应。当在-78°C下于THF中进行反应时,三[2-(2-甲氧基乙氧基)乙基]胺(TDA-1)被证明是有效的添加剂。1与芳族醛的缩合反应得到的选择性接近95%。已经报道了在该反应中使用5倍过量的18C6。但是,我们定义了仅需要催化量的条件。