An Improved Synthesis of 5-Ethenyl-4a-methyl-2-oxo-2,3,4,4a,7,8-hexahydronaphthalene and Similar 1,3-Dienes using Palladium Catalyzed Cross-Coupling Methodology
Enol triflates derived from the Wieland–Miescher ketone and an analog bearing an angular acetoxymethyl group: their highly regioselective synthesis and Stille coupling with vinyl(tributyl)tin
作者:Nicolas Zorn、Robert Lett
DOI:10.1016/j.tetlet.2006.03.185
日期:2006.6
A highly selective synthesis of the enol triflate derived from the 9-keto group was achieved directly from the Wieland–Miescher ketone or an analog in kinetic conditions with LHMDS/THF–HMPA and Comins reagent. The other isomeric triflates were also obtained selectively in other conditions and their specific Stille coupling with vinyl(tributyl)tin was achieved in high yields. The structures of the different
直接从Wieland-Miescher酮或类似物在动力学条件下使用LHMDS / THF-HMPA和Comins试剂可高度选择性地合成9-酮基衍生的烯醇三氟甲磺酸酯。还可以在其他条件下选择性地获得其他异构体三氟甲磺酸酯,并以高收率实现了它们与乙烯基(三丁基)锡的特定斯蒂勒偶联。通过IR,UV,1 H和13 C NMR(COSY,HMBC,HSQC和NOE)明确确定不同异构体的结构。由于结构分配错误,Pal先前报告的Wieland–Miescher酮的结果必须予以纠正。