Regiocontrolled Coupling of Aromatic and Vinylic Amides with α-Allenols To Form γ-Lactams via Rhodium(III)-Catalyzed C–H Activation
作者:Zhi Zhou、Guixia Liu、Xiyan Lu
DOI:10.1021/acs.orglett.6b02903
日期:2016.11.4
rhodium(III)-catalyzed C–H activation has been demonstrated. This [4 + 1] annulationreaction provides an efficient method for the synthesis of isoindolinones and 1,5-dihydro-pyrrol-2-ones bearing a tetrasubstituted carbon atom α to the nitrogen atom with good functional group tolerance. The hydroxyl group in the allene substrate is essential in controlling the chemo- and regioselectivity of the reaction probably by
and expeditious protocol for the synthesis of diverse difunctionalized indenones through rhodium-catalyzed C–H activation and multistep cascade reaction of benzimidates and alkenes has been developed. The transformation involves the cleavage and formation of multiple bonds in one pot under mild reaction conditions, and Mn(OAc)2 plays an important role in the reaction.
作者:Qing-Gang Tang、Sen-Lin Cai、Chuan-Chuan Wang、Guo-Qiang Lin、Xing-Wen Sun
DOI:10.1021/acs.orglett.0c00779
日期:2020.5.1
A simple, direct, and highly enantioselective synthesis of spiro-oxindole piperidin-2-one derivatives was achieved through an aza-Michael/Michael cyclizationcascade sequence using a squaramide catalyst. The desired products were obtained in excellent yields (up to 99%) and good to high stereoselectivities (up to >20:1 dr and up to 99% ee) under mild conditions.
使用方酰胺催化剂通过氮杂迈克尔/迈克尔环化级联序列实现了螺-羟吲哚哌啶-2-酮衍生物的简单、直接和高度对映选择性合成。在温和条件下以优异的收率(高达 99%)和良好的立体选择性(高达 >20:1 dr 和高达 99% ee)获得所需的产物。
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-Alkoxyacrylamides in Domino Reactions: Catalytic and Stereoselective Access to δ-Lactams
The use of N‐alkoxyacrylamides in a domino aza‐Michael/intramolecular‐Michael reaction for the synthesis of δ‐lactams is presented. This base‐catalyzed process operates under mild conditions and the polysubstituted aza‐heterocycles are isolated in good yields with good to excellent stereocontrol.
Rhodium(III) Catalyzed Carboamination of Alkenes Triggered by C–H Activation of <i>N</i>-Phenoxyacetamides under Redox-Neutral Conditions
作者:Zhiyong Hu、Xiaofeng Tong、Guixia Liu
DOI:10.1021/acs.orglett.6b00616
日期:2016.4.1
N-Alkoxyacrylamides are coupled with N-phenoxyacetamides by RhIII catalysis through C–H functionalization and amido group transfer under external oxidant-free conditions, which affords acyclic alkene carboamination products in an atom-economical way. Mechanisticinsight into this transformation indicates the amide group in N-alkoxyacrylamide plays a critical role in this C–C/C–N bond formation reaction