一系列含有环戊烯环或杂环的2-炔基羰基化合物可通过1,2-烷基迁移过程转化为各种稠合的二氢苯并呋喃和四氢呋喃[2,3- c ]吡啶。当使用阳离子金(I)催化剂时,这两个反应都具有出色的区域选择性和立体选择性。在不同条件下处理4-苯乙烯基环戊-1-烯羧酸酯可提供一系列高度官能化的二氢苯并呋喃和二氢异苯并呋喃。观察到产物选择性的差异,这取决于所用银盐的阴离子。有趣的是,环-稠合四氢喹啉通过C的手段仅经历-1,2'-烷基迁移反应C裂解/环化序列以提供四氢a庚因衍生物。机理研究表明,金络合物通过协同反应途径催化1,2-烷基迁移反应,并通过逐步反应途径催化1,2'-烷基迁移反应。
Furan‐Based
<i>o‐</i>
Quinodimethanes by Gold‐Catalyzed Dehydrogenative Heterocyclization of 2‐(1‐Alkynyl)‐2‐alken‐1‐ones: A Modular Entry to 2,3‐Furan‐Fused Carbocycles
strategy for in situ generation of furan‐based ortho‐quinodimethanes (o‐QDMs) by the gold(I)‐mediated dehydrogenative heterocyclization of 2‐(1‐alkynyl)‐2‐alken‐1‐ones in the presence of pyridine N‐oxide under mild reaction conditions was developed. These in situ furan‐based o‐QDMs were trapped by electron‐deficient olefins and alkynes, thus furnishing various 2,3‐furan‐fused carbocycles in good yields