Efficient synthesis of oxindoles by thermal and rhodium(II)-catalyzed Wolff rearrangement
摘要:
An efficient synthesis of oxindoles is achieved from a thermal and rhodium(II)-catalyzed Wolff rearrangement of diazoquinolinediones in moderate yields. (C) 1999 Elsevier Science Ltd. All rights reserved.
Rhodium-Mediated Dipolar Cycloaddition of Diazoquinolinediones
摘要:
As an entry to furoquinoline structures of natural origin, the rhodium-mediated dipolar cycloaddition of diazoquinolinediones with alkenes and alkynes has been examined. Because of the unsymmetrical nature of the diazo compounds, both linear and angular furoquinoline products are possible. For the most part, a mixture of regioisomers is generated in moderate to good yields, though in a few cases dominant products are obtained in high yields. The products can be further converted to naturally occurring alkaloids such as isodictamnine. A novel observation in this work is that catalytic quantities of acid enhance the yield and regiochemical control in the cycloaddition.
Synthesis of diverse isatins via ring contraction of 3-diazoquinoline-2,4-diones
作者:Rajeev Shrestha、Gun Joon Lee、Yong Rok Lee
DOI:10.1039/c6ra13585d
日期:——
An efficient synthesis of diverse isatin derivatives was accomplished by a copper-mediated reaction of 3-diazoquinoline-2,4-diones viaringcontraction through domino Wolff rearrangement, decarboxylation, bromination, substitution, and dehydration. This protocol has several advantages as a one-pot procedure, with functional group tolerance, and high yield.
One-pot construction of diverse and functionalized isochromenoquinolinediones by Rh(<scp>iii</scp>)-catalyzed annulation of unprotected arylamides with 3-diazoquinolinediones and their application for fluorescence sensor
作者:Rajeev Shrestha、Hari Datta Khanal、Yong Rok Lee
DOI:10.1039/c9ra03146d
日期:——
efficient Rh(III)-catalyzed annulation of arylamides with 3-diazoquinolinediones for the construction of diverse and highly functionalized isochromenoquinolinediones is described. Furthermore, the methodology is applicable for delivering various relevant molecules such as pyridopyranoquinolindiones, thienopyranoquinolinones, and indolopyranoquinolinone. The reaction proceeds viacascadeC–Hactivation, carbene
描述了一种简便高效的 Rh( III ) 催化芳基酰胺与 3-重氮喹啉二酮的环化,用于构建多种高度功能化的异色烯喹啉二酮。此外,该方法适用于传递各种相关分子,如吡喃并吡喃喹啉二酮、噻吩并吡喃喹啉酮和吲哚吡喃喹啉酮。该反应通过级联 C-H 活化、卡宾插入和分子内内酯化进行。该反应具有高原子经济性、良好的官能团耐受性和高区域选择性。合成的化合物还可以作为 Fe 3+离子的有效荧光传感器。
Rhodium(III)‐Catalyzed Regioselective C−H Activation/Annulation for the Diverse Pyrazole‐Core Substituted Furans
作者:Hongyun Cai、Raju S. Thombal、Xin Li、Yong Rok Lee
DOI:10.1002/adsc.201900498
日期:2019.9.3
method for polyfunctionalized furans involving rhodium(III)‐catalyzed pyrazole‐ or indazole‐directed dual C−H functionalization with diazodicarbonyls has been developed. This strategy provides rapid access to diverse tetrasubstituted furans bearing various pyrazoles or indazoles. This unprecedented one‐pot protocol proceeds via cascade C−Hactivation, metal‐carbene formation, migratory insertion, intramolecular
Ruthenium(II)-Catalyzed Protocol for Preparation of Diverse α,β- and β,β-Dihaloenones from Diazodicarbonyls
作者:Krishna Bahadur Somai Magar、Yong Rok Lee
DOI:10.1002/adsc.201400348
日期:2014.11.3
AbstractEfficient one‐step syntheses of α,β‐ and β,β‐dihaloenones were achieved by ruthenium(II)‐catalyzed reactions between cyclic or acyclic diazodicarbonyl compounds and oxalyl chloride or oxalyl bromide in moderate to good yields. This methodology offers several significant advantages, which include ease of handling, mild reaction conditions, one‐step reaction, and the use of an effective and non‐toxic catalyst. The synthesized compounds were further transformed into highly functionalized novel molecules bearing aromatic rings on the enone moiety using the Suzuki reaction.magnified image
Rhodium-Mediated Dipolar Cycloaddition of Diazoquinolinediones
作者:Michael C. Pirrung、Florian Blume
DOI:10.1021/jo982503h
日期:1999.5.1
As an entry to furoquinoline structures of natural origin, the rhodium-mediated dipolar cycloaddition of diazoquinolinediones with alkenes and alkynes has been examined. Because of the unsymmetrical nature of the diazo compounds, both linear and angular furoquinoline products are possible. For the most part, a mixture of regioisomers is generated in moderate to good yields, though in a few cases dominant products are obtained in high yields. The products can be further converted to naturally occurring alkaloids such as isodictamnine. A novel observation in this work is that catalytic quantities of acid enhance the yield and regiochemical control in the cycloaddition.