Scope and Mechanism of Direct Indole and Pyrrole Couplings Adjacent to Carbonyl Compounds: Total Synthesis of Acremoauxin A and Oxazinin 3
作者:Jeremy M. Richter、Brandon W. Whitefield、Thomas J. Maimone、David W. Lin、M. Pilar Castroviejo、Phil S. Baran
DOI:10.1021/ja074392m
日期:2007.10.1
Full details are provided for a recently invented method to couple indoles and pyrroles to carbonyl compounds. The reaction is ideally suited for structurally complex substrates and exhibits high levels of chemoselectivity (functional group tolerability), regioselectivity (coupling occurs exclusively at C-3 of indole or C-2 of pyrrole), stereoselectivity (substrate control), and practicality (amenable
提供了最近发明的将吲哚和吡咯与羰基化合物偶联的方法的全部细节。该反应非常适合结构复杂的底物,并表现出高水平的化学选择性(官能团耐受性)、区域选择性(偶联仅发生在吲哚的 C-3 或吡咯的 C-2)、立体选择性(底物控制)和实用性(适合)以扩大规模)。此外,四元立构中心很容易且可预测地生成。该反应已应用于许多合成问题,包括天然产物 hapalindole 家族成员、酮咯酸、acremoauxin A 和恶嗪宁 3 的全合成。从机理上讲,该偶联方案似乎通过需要生成的单一电子转移过程来操作与羰基相邻的缺电子自由基,然后被吲哚或吡咯阴离子拦截。