Synthesis of pyrazolo[5,1-a]isoquinolines via a silver(<scp>i</scp>)-catalyzed reaction of (1-arylethylidene)hydrazides with N′-(2-alkynylbenzylidene)hydrazides
作者:Xinxing Gong、Jie Wu
DOI:10.1039/c5ob01972a
日期:——
es is reported, which provides an efficient approach for the synthesis of pyrazolo[5,1-a]isoquinolines. During the reaction process, azo-alkene and isoquinolinium-2-yl amide acted as the key intermediates, which then underwent [3 + 2] cycloaddition and intramolecular rearrangement leading to the corresponding pyrazolo[5,1-a]isoquinolines. Azo-alkene would be formed in situ from (1-arylethylidene)hydrazide
报道了银(I)催化的(1-芳基亚乙基)酰肼与N '-(2-炔基亚苄基)酰肼的反应,这为吡唑并[5,1- a ]异喹啉的合成提供了一种有效的方法。在反应过程中,偶氮烯烃和异喹啉-2-基酰胺充当关键中间体,然后进行[3 + 2]环加成和分子内重排,生成相应的吡唑并[5,1- a ]异喹啉。在I 2和TBHP存在下,偶氮烯会由(1-芳基亚乙基)酰肼在原位形成,而异喹啉鎓-2-基酰胺将通过银(I)促进的6-位原位生成。远藤的环化Ñ ' - (2- alkynylbenzylidene基)酰肼。这种转化在温和条件下可以顺利进行,并且可以耐受各种官能团。
Synthesis of H-pyrazolo[5,1-a]isoquinolines via a silver triflate-catalyzed tandem reaction of N′-(2-alkynylbenzylidene)hydrazide with alcohol
作者:Wenyan Hao、Tinli Zhang、Mingzhong Cai
DOI:10.1016/j.tet.2013.08.049
日期:2013.11
A silver triflate-catalyzed tandemreaction of N′-(2-alkynylbenzylidene)hydrazide with alcohol is reported, which generates H-pyrazolo[5,1-a]isoquinoline derivatives in good yields under mild conditions.