Pd-catalyzed cross-coupling of allylsilane-vinylcopper species with aryl and vinyl halides: the first total synthesis of (−)-nomadone
作者:Francisco J. Pulido、Asunción Barbero、Carlos García
DOI:10.1016/j.tet.2009.01.118
日期:2009.7
The reaction of allene with a lower order silylcuprate 3 leads to an allylsilane-vinylcopper intermediate 4, which undergoes palladium-catalyzed cross-coupling reaction with both vinyl and aryl halides. The influence of several factors such as the nature of the transition metal used as catalyst, the temperature of the reaction, and the order of addition are studied. This simple methodology allows the
丙二烯与低级甲硅烷基铜酸酯3的反应生成烯丙基硅烷-乙烯基铜中间体4,该中间体进行钯催化的与乙烯基卤化物和芳基卤化物的交叉偶联反应。研究了几种因素的影响,例如用作催化剂的过渡金属的性质,反应温度和添加顺序。这种简单的方法可以一步合成异戊二烯基硅烷,可以方便地将其与不同的异戊二烯醛偶联,得到几种无环的天然萜烯。因此,我们能够从艾伦中分两步合成天然单萜(±)-ipsdienol和(±)-ipsenol,这是树皮甲虫Ips paraconfusus的聚集信息素的主要成分。。另一方面,异戊二烯基硅烷7与天然单萜(S)-香茅醛的烯丙基封端反应生成中间体,该中间体很容易在两个几乎定量的步骤中转化为天然倍半萜(-)-Nomadone。游牧民倍半萜是诺曼达蜜蜂的头腺分泌物的组成部分。据我们所知,这是第一个报道的(-)-游豆酮的全合成。