BX3-Mediated Intermolecular Formation of Functionalized 3-Halo-1H-indenes via Cascade Halo-Nazarov-Type Cyclization
作者:Rodney A. Fernandes、Anupama Kumari
DOI:10.1055/s-0039-1690881
日期:2020.8
inexpensive reagents and a convenient and mild reaction procedure to generate halo-functionalized indenes (45 examples). The reaction was also extended to 8-formylcoumarins to deliver coumarin-based 3-halo-1H-indenes in 79–95% yield (6 examples). The reaction involves conversion of the aldehyde into an sp3 carbon with two new C–C bonds and additionally a C–X bond is formed (X = halide).
已经开发了由BX 3促进的由4-氧代-4 H-亚甲基苯甲醛和炔烃3-卤代官能化的1 H-茚的分子间区域选择性合成。BX 3表现出路易斯酸催化剂和卤化物源的双重作用,可用于卤代-Nazarov型环化反应。整个转化过程代表了一种有效的级联环状反应,它采用了容易获得的起始原料,廉价的试剂以及便捷而温和的反应程序来生成卤官能化的茚满(45个例子)。该反应还扩展到8-甲酰基香豆素,以提供基于香豆素的3-卤代-1 H-茚的产率为79–95%(6个示例)。该反应涉及通过两个新的C–C键将醛转化为sp 3碳,并另外形成C–X键(X =卤化物)。