proceeded smoothly using stoichiometric amounts of BuLi. Both aminolithiation and carbolithiation were in equilibrium at room temperature, and the stereochemistry of the cyclization was thermodynamically controlled. At –78 °C the reaction was kinetically controlled and the cyclized product, 1,2-disubstituted octahydroindolizine, was obtained with good diastereoselectivity.
使用
化学计量量的 BuLi,带有
乙烯基硫化物部分的
氨基烯烃的
氨基
锂化 - 碳
锂化串联环化可以顺利进行。
氨基
锂化和碳
锂化在室温下均处于平衡状态,环化的立体
化学受热力学控制。在–78 °C 时,反应受到动力学控制,并以良好的非对映选择性获得环化产物 1,2-二取代八氢
茚茚。