Enantioselective Synthesis of Epi-Emetine Analogues: Control of the Facial Selectivity in a Three-Component Domino Knoevenagel-Hetero-Diels-Alder Reaction*
作者:Lutz F. Tietze、Nils Rackelmann
DOI:10.1515/znb-2004-0415
日期:2004.4.1
2 and enol ether 3 leads to the cycloadduct rac-17 as the main product which in a second domino process was transformed into the benzoisoquinolizidine rac-18 by solvolysis, hydrogenolysis, condensation and hydrogenation; rac-18 was used as a substrate for the synthesis of the two diastereomeric epiemetine analogues 9 and 10 with > 96% ee (9) and 80% ee (10), respectively, by condensation with the phenylethylamine
摘要 醛 rac-8、Meldrum 酸 2 和烯醇醚 3 的多米诺 Knoevenagel-hetero-Diels-Alder 反应生成环加合物 rac-17 作为主要产物,该产物在第二个多米诺过程中转化为苯并异喹唑啉 rac-18通过溶剂分解、氢解、缩合和加氢;通过与苯乙胺 23 缩合、Bischler-Napieralski 反应和 rac-18 分别用作合成两种非对映异构表皮米汀类似物 9 和 10(具有 > 96% ee (9) 和 80% ee (10))的底物使用手性催化剂 (R,R)-26 进行“对映选择性”氢化。