Visible-light-induced cascade dearomatization cyclization between alkynes and indole-derived bromides: a facile strategy to synthesize spiroindolenines
A visible-light-initiated intermolecular dearomatization cyclization cascade reaction between alkynes and indole-derived bromides has been explored. This transformation exhibits a wide substrates scope and significant functional groups tolerance, providing an efficient way to access a variety of spiroindolenines under mild conditions.
method with CDMT enabled the sequential transformation of gramines: substitution with (N-alkylidene)aminomalonates followed by the Pictet–Spengler reaction under acidic conditions afforded 1,2,3,4-tetrahydro-β-carboline derivatives in one pot.
Dearomative Cycloadditions Utilizing an Organic Photosensitizer: An Alternative to Iridium Catalysis
作者:Alessa B. Rolka、Burkhard Koenig
DOI:10.1021/acs.orglett.0c01622
日期:2020.7.2
A highly efficient, cheap, and organic alternative to the commonly used iridium photosensitizer (Ir[dF(CF3)ppy]2(dtbpy))PF6 ([Ir–F]) is presented for visible-light energy transfer catalysis. The organicdye 2CzPN surpasses [Ir–F] in selectivity while at the same time being easily accessible in one step. The catalyst is recyclable and, due to its uncharged nature, soluble in nonpolar solvents such as
I<sub>2</sub>-induced cascade cyclization and dearomatization of indoles for the highly efficient synthesis of iodinated and vinylic spiroindolenines
作者:Xiaohui Wei、Xuewu Liang、Yazhou Li、Qi Liu、Xuyi Liu、Yu Zhou、Hong Liu
DOI:10.1039/d1gc02713a
日期:——
framework is a privileged heterocyclic motif and is widely present in numerous indole alkaloids. Herein, we develop a metal-free and environmentally friendly approach for the intramolecular cascade cyclization and dearomatization of indole derivatives to selectively afford iodinated and vinylic spiroindolenines by a substrate-controlled strategy. Simple operation, mild conditions, and high yield make this
Deaminative Arylation and Alkenyaltion of Aliphatic Tertiary Amines with Aryl and Alkenylboronic Acids via Nitrogen Ylides
作者:Jianke Su、Chengbo Li、Xinyuan Hu、Yu Guo、Qiuling Song
DOI:10.1002/anie.202212740
日期:2022.12.23
arylation and alkenylation of tertiary amines with aryl and alkenylboronic acids is enabled by difluorocarbene under transition-metal-free conditions. This protocol represents a novel reaction mode which succeeded in the construction of Csp3−Csp2 bonds via an in situ formed nitrogen ylide from tertiary amines (propargylamines, allylamines and 1H-indol-3-yl methane amines) and difluorocarbene with aryl and
在无过渡金属的条件下,二氟卡宾能够实现叔胺与芳基和烯基硼酸的有效且通用的脱氨芳基化和烯基化。该协议代表了一种新的反应模式,它通过叔胺(炔丙基胺、烯丙基胺和 1H-吲哚-3-基甲烷胺)和二氟卡宾原位形成的氮叶立德成功地构建了 C sp 3 -C sp 2键与芳基和烯基硼酸。