Internal Nucleophilic Catalyst Mediated Cyclisation/Ring Expansion Cascades for the Synthesis of Medium‐Sized Lactones and Lactams
作者:Aggie Lawer、James A. Rossi‐Ashton、Thomas C. Stephens、Bradley J. Challis、Ryan G. Epton、Jason M. Lynam、William P. Unsworth
DOI:10.1002/anie.201907206
日期:2019.9.23
for the synthesis of medium-sized lactones and lactams from linear precursors is described in which an amine acts as an internal nucleophilic catalyst to facilitate a novel cyclisation/ring expansion cascade sequence. This method obviates the need for the high-dilution conditions usually associated with medium-ring cyclisation protocols, as the reactions operate exclusively via kinetically favourable
描述了一种由线性前体合成中型内酯和内酰胺的策略,其中胺充当内部亲核催化剂,以促进新型环化/扩环级联序列。该方法避免了通常与中环环化方案相关的高稀释条件的需要,因为反应仅通过动力学上有利的“正常”尺寸的循环过渡态进行。该相同特征还使得能够通过点对轴手性转移以完全的对映选择性来制备含联芳基的中型环。