Hydrazone-oxime Selectively Directed Redox-Neutral [4 + 2] Annulations Cascade with Alkynes and Iodonium Ylides to Build 1,1′-Biisoquinoline Mono-<i>N</i>-oxides
作者:Chaoying Wen、Yuqin Wang、Yanyan Yang、Ya-Nan Tian、Jinhua Wang、Shiqing Li
DOI:10.1021/acs.orglett.3c00590
日期:2023.4.21
directing groups is an important but challenging issue in organic chemistry. Herein, a combined directing group (hydrazone-oxime) selectively directed [4 + 2] annulation cascade to synthesize novel 1,1′-biisoquinoline mono-N-oxides has been developed. Owing to the subtle differences in electronic properties between hydrazone and oxime, the first C–H annulation with alkynes preferentially occurs at the hydrazone
包含多个定向基团的分子的选择性 C-H 活化是有机化学中一个重要但具有挑战性的问题。在此,联合导向基团(腙-肟)选择性地导向 [4 + 2] 环化级联合成新型 1,1'-双异喹啉单-N- 氧化物已被开发出来。由于腙和肟之间电子性质的细微差别,与炔烃的第一次 C-H 环化优先发生在腙侧形成 1-肟基异喹啉,然后在肟侧与碘叶立德进行第二次 C-H 环化. 两个 [4 + 2] 环化在氧化还原中性条件下顺利进行,可以在一锅中进行,无需使用化学计量的外部氧化剂。此外,已经进行了 ESI-MS 和 DFT 计算以证实反应机理。这种新颖的双异喹啉骨架可以为未来具有合成价值的研究前景铺平道路。