Intramolecular Dehydrative Coupling of Tertiary Amines and Ketones Promoted by KO-<i>t</i>-Bu/DMF: A New Synthesis of Indole Derivatives
作者:Wen-tao Wei、Xue-jiao Dong、Shao-zhen Nie、Yan-yan Chen、Xue-jing Zhang、Ming Yan
DOI:10.1021/ol402908m
日期:2013.12.6
A new synthesis of indole derivatives has been achieved through intramolecular dehydrative coupling of tertiary amines and ketonespromoted by KO-t-Bu/DMF. The reaction probably proceeds via an α-amino alkyl radical pathway.
通过KO- t- Bu / DMF促进的叔胺和酮的分子内脱水偶联,实现了吲哚衍生物的新合成。该反应可能通过α-氨基烷基自由基途径进行。
Brønsted acid cocatalysis in photocatalytic intramolecular coupling of tertiary amines: efficient synthesis of 2-arylindols
作者:Xiaoqian Yuan、Xinxin Wu、Shupeng Dong、Guibing Wu、Jinxing Ye
DOI:10.1039/c6ob01239f
日期:——
We report herein a highly efficient intramolecular coupling reaction of tertiaryamines and ketones (α,β-unsaturated ketones) by using a Brønsted acid as a cocatalyst, affording 2-arylindols in good to excellent yields (up to 92%) under visible light irradiation at room temperature.
A catalytic amount of triarylaminium salt is demonstrated to be an efficient initiator for oxidative Mannich reaction of tertiary amines and nonactivated ketones under mild neutral conditions. Air is essential for this reaction and acts as a terminal oxidant. Metal catalysts, acid or base additives, and stoichiometric amounts of chemical oxidants are all avoided in this methodology. Six examples of
Unprecedented constructions of C═Cdouble bonds have been achieved by Ir-catalyzed intramolecular dehydrogenative and dehydrative cross-coupling of tertiary amines and ketones. The reactions are proposed to proceed via an Ir-mediated C–H activation mechanism.