Selective <i>Ortho</i> and Benzylic Functionalization of Secondary and Tertiary <i>p</i>-Tolylsulfonamides. <i>Ipso</i>-Bromo Desilylation and Suzuki Cross-Coupling Reactions
作者:Stephen L. MacNeil、O. B. Familoni、Victor Snieckus
DOI:10.1021/jo001402s
日期:2001.6.1
Kinetic vs thermodynamic deprotonation studies on secondary and tertiary sulfonamides 1 and 2 using n-BuLi have been carried out. While both 1 and 2 show kinetic ortho-metalation, thermodynamic conditions lead to ortho and benzylic deprotonation, respectively (Figures 1 and 2). Metalation of 1 using the n-BuLi/KOtBu superbase led to regioselective benzylic metalation (Figure 4); LDA deprotonation was
已使用n-BuLi对仲磺酰胺1和叔磺酰胺2进行了动力学与热力学去质子研究。虽然1和2均显示动力学原位金属化,但热力学条件分别导致原位和苄基去质子化(图1和2)。使用n-BuLi / KOtBu超碱金属化1会导致区域选择性苄基金属化(图4);还简要探讨了LDA的去质子化。所开发条件的应用允许合成多种磺酰胺产物5a-e,6a-e,7a,b和8a-e。异丙基-溴脱甲硅基反应得到磺酰胺9a,b,而铃木的交叉偶联反应得到联芳基磺酰胺11a-c。