developed for the synthesis of 2-acylquinolines from methyl ketones and arylamines using 1,4-dithane-2,5-diol as an ethylene surrogate. Moreover, the investigation of the mechanism suggested that this reaction occurred via an iodination/Kornblum oxidation/Povarov/aromatization sequence. It is noteworthy that the arylamine substrate also played an important role in promoting the reaction.
The first synthesis of 2,3-diaroyl quinolines via a formal [3 + 2 + 1] cycloaddition of enaminones, aryl methyl ketones, and aryl amines is disclosed. This reaction efficiently affords a 1,4-dicarbonyl scaffold, which is a useful building block for constructing complex fused heterocycles. Furthermore, the 1,4-dicarbonyl scaffold has been used directly to prepare pyridazino[4,5-b]quinoline skeletons
公开了通过烯胺酮,芳基甲基酮和芳基胺的正式[3 + 2 + 1]环加成的2,3-二酰基酰基喹啉的首次合成。该反应有效地提供了1,4-二羰基支架,这是用于构建复杂的稠合杂环的有用的构建基。此外,已将1,4-二羰基支架直接用于一锅制备哒嗪并[4,5- b ]喹啉骨架。
An unusual 1,2-aryl shift in palladium-catalyzed cross-coupling ethoxycarbonylation of arylboronic acids with α-iminoesters
The Pd-catalyzed cross-coupling ethoxycarbonylation of aryl boronic acids with N-aryl-α-iminoesters affords aryl carboxylic esters via carbonyl-imino Ï bond cleavage. This unprecedented mode of reaction allows regioselective installation of the ethoxycarbonyl group into target molecules. Mechanism studies have revealed that an unusual 1,2-aryl shift process is involved in the transformation.
Iodine-Promoted N–H/α,β-C(sp<sup>3</sup>)-Trifunctionalization of <scp>l</scp>-Proline: Access to 3,4-Dihydrobenzo[<i>b</i>][1,7]naphthyridines via Consecutive Decarboxylation/Ring Opening/Dicyclization
proceeding through an iodine-promoted consecutive decarboxylation/ring-opening/dicyclization process, is achieved. This strategy affords structurally diverse fused N-heterocycles in good yields with a wide substrate scope. Preliminary mechanistic studies indicate that catabolism of l-proline might be involved in this cascade reaction and the in situ generated intermediate 4-aminobutanal was identified
Synthesis of 1,4‐Benzothiazines via KI/DMSO/O
<sub>2</sub>
‐Mediated Three‐Component Oxidative Cyclization/Coupling
作者:Jinwu Zhao、Zhigao Luo、Jingxiu Xu
DOI:10.1002/adsc.202000201
日期:2020.5.12
for the generation of 1,4‐benzothiazines is reported herein. The KI/DMSO/O2 system was found to be effective for the oxidative cyclization/coupling of 2‐aminobenzenethiols, anilines, and methylketones. Hence, various structurally important imino 1,4‐benzothiazines were assembled with broad functional group tolerance. Mechanistic studies revealed an initial oxidation of ketoneα C−H bonds by the KI/DMSO/O2
本文报道了一种用于生成1,4-苯并噻嗪的三组分无过渡金属好氧方法。发现KI / DMSO / O 2系统对于2-氨基苯硫醇,苯胺和甲基酮的氧化环化/偶联有效。因此,组装了具有重要官能团耐受性的各种结构上重要的亚氨基1,4-苯并噻嗪。机理研究表明,KI / DMSO / O 2氧化体系使酮αC-H键初步氧化。