Preparation of Perhydroisoquinolines via the Intramolecular Diels−Alder Reaction of <i>N</i>-3,5-Hexadienoyl Ethyl Acrylimidates: A Formal Synthesis of (±)-Reserpine
作者:Steven M. Sparks、Arnold J. Gutierrez、Kenneth J. Shea
DOI:10.1021/jo0341362
日期:2003.6.1
The intramolecular Diels-Alder reaction of N-3,5-hexadienoyl ethyl acrylimidates provides an efficient method for the synthesis of cis-fused hexahydroisoquinolones. As a demonstration of the stereochemical control offered by this cycloaddition, two approaches to the construction of the DE rings of reserpine are reported. In the second entry, N-((4-(trimethylsilyl)ethoxymethoxy)methyl-6-benzyloxy-3Z
N-3,5-己二酰基丙烯酰胺酯的分子内Diels-Alder反应提供了一种合成顺式稠合六氢异喹诺酮的有效方法。作为这种环加成反应提供的立体化学控制的证明,报道了两种构建利血平DE环的方法。在第二项中,对N-((4-(三甲基甲硅烷基)乙氧基甲氧基)甲基-6-苄氧基-3Z,5E-己二酰基)-1-氮杂-2-乙氧基-1,3-丁二烯(40)进行环加成反应,生成主要产物(4aS,7R,8aS)-7-苄氧基-5-((2-三甲基甲硅烷基)乙氧基甲氧基)甲基-3,4,4a,7,8,8a-六氢异喹啉-3-酮(41)。然后将Cycloadduct 41立体定向修饰为(4aS,5S,6R,7R,8aR)-6-甲氧基-5-甲氧基羰基-7-(3,4,5-三甲氧基)苯甲酰基癸烯二异喹啉-2-羧酸甲酯(3) ,