approach for the synthesis of polysubstituted pyridines has been achieved through copper-catalyzed oxidative sp3 C–H coupling of oxime acetates with toluene derivatives. Besides, benzylamine and p-toluenesulfonylhydrazone were also introduced to react with oxime acetates to enrich the diversity of this synthetic method. These transformations provide highly flexible and facile preparation of substituted pyridines
Metal-Free Synthesis of 2,4,6-Trisubstituted Pyridines via Iodine-Initiated Reaction of Methyl Aryl Ketones with Amines under Neat Heating
作者:Ze Zhang、Hui Xu、Ji-Chao Zeng、Fang-Jian Wang
DOI:10.1055/s-0036-1588380
日期:——
HI-catalyzed) condensation of methyl aryl ketones with amines and the following cyclization-aerobic oxidation. Large-scale synthesis and mechanistic investigation were also performed. A neat heating protocol has been developed for metal-free synthesis of various 2,4,6-trisubstituted pyridines via iodine-initiated (in situ generated HI-catalyzed) condensation of methyl aryl ketones with amines and the following
TMSOTf-mediated Kröhnke pyridine synthesis using HMDS as the nitrogen source under microwave irradiation
作者:Chieh-Kai Chan、Yi-Hsiu Chung、Cheng-Chung Wang
DOI:10.1039/d2ra00084a
日期:——
An efficient protocol for the preparation of pyridine skeletons has been successfully developed involving the TMSOTf/HMDS (trifluoromethanesulfonic acid/hexamethyldisilane) system for the intermolecular cyclization of chalcones under MW (microwave) irradiation conditions. This method provides a facile approach to synthesize 2,4,6-triaryl or 3-benzyl-2,4,6-triarylpyridines in good to excellent yields
Merrifield resin-supported quinone as an efficient biomimetic catalyst for metal-free, base-free, chemoselective synthesis of 2,4,6-trisubstituted pyridines
作者:Qing Yang、Yilin Zhang、Wei Zeng、Zheng-Chao Duan、Xinxin Sang、Dawei Wang
DOI:10.1039/c9gc02409c
日期:——
(EDX). This supported quinone catalyst exhibited excellent catalytic reactivity for chemoselective synthesis of 2,4,6-trisubstitutedpyridines, providing an efficient and green method for the synthesis of pyridinederivatives under mild conditions. Mechanistic investigations were conducted to gain insights into the heterogeneous biomimetic catalyst as well as the resulting transformation. The successful
Acid-controlled multicomponent selective synthesis of 2,4,6-triaryl pyridines and pyrimidines by using hexamethyldisilazane as a nitrogen source under microwave irradiation
作者:Chieh-Kai Chan、Yi-Hsiu Chung、Cheng-Chung Wang
DOI:10.1039/d2ra04739j
日期:——
protocol for the synthesis of functionalized 2,4,6-triaryl pyridines and pyrimidines was developed from commercially available aromatic ketones, aldehydes and hexamethyldisilazane (HMDS) as a nitrogen source undermicrowave irradiation. In this multicomponent synthetic route, Lewis acids play an important role in selectively synthesizing six-membered heterocycles, including pyridines (1N) and pyrimidines