Facile Regioselective Synthesis of Pyrazolo[5,1-<i>a</i>]isoquinolines via Ring-Opening Cyclization/Oxidation Reactions of Stable Aroyldiaziridines of 3,4-Tetrahydroisoquinoline with Alkynes
作者:Howard Alper、Heriberto Ortega、Sara Ahmed
DOI:10.1055/s-2007-990888
日期:2007.12
4-tetrahydroisoquinolines undergo regioselective cycloaddition reactions with a number of both mono and disubstituted alkynes, affording five-membered ring products which, after oxidative aromatization of the pyrazoline ring, lead to the efficient preparation of pyrazolo[5,1-a]isoquinolines. The overall transformation is base-catalyzed and occurs more rapidly in the presence of oxygen, in halogenated
Catalyst-free and oxidant-free tandem aza-Mannich/cyclization/aromatization of <i>C</i>,<i>N</i>-cyclic azomethine imines with enamides: facile synthesis of 5,6-dihydropyrazolo[5,1-<i>a</i>]isoquinolines
作者:Hao Dong、Yongxing Zhang、Xiaochen Tian、Ruochen Pang、Weiwu Ren、Yang Wang
DOI:10.1039/d2gc01275h
日期:——
tandem aza-Mannich/cyclization/aromatization reaction of C,N-cyclic azomethine imines with enamides has been developed. This practical one-step protocol enables a simple and environmentally friendly route toward the straightforward synthesis of highly substituted 5,6-dihydropyrazolo[5,1-a]isoquinolines. Different types of enamides and enamines, especially enamides derived from marketed drugs as well as bioactive
开发了一种新型高效的无催化剂、无氧化剂串联氮杂曼尼希/环化/芳构化C , N-环偶氮甲亚胺与烯酰胺反应。这种实用的一步法为直接合成高度取代的 5,6-二氢吡唑并[5,1- a ] 异喹啉提供了一种简单且环保的途径。不同类型的烯酰胺和烯胺,尤其是衍生自上市药物以及生物活性分子的烯酰胺,是合适的底物。CB1 大麻素受体拮抗剂可以基于该方法有效合成,说明这将是合成有价值的结构基序的实用策略。
Regioselectivity Control in the Oxidative Formal [3 + 2] Annulations of Ketoxime Acetates and Tetrohydroisoquinolines
A novel copper-catalyzed oxidative formal [3 + 2] annulations of ketoximeacetates and tetrohydroisoquinolines for the synthesis of fused pyrazoles and imidazoles has been developed. A broad range of important isoquinoline-fused pyrazole and imidazole products were selectively generated by the key control of oxidant.