A regioselective approach for construction of 5-membered and 6-membered flavonoid is established by Pd catalyzed carbonylative cyclization of 2-iodophenol with terminal alkynes using different amine bases under mild reaction condition. The catalytic experiments found that piperazine preferentially accelerate 6-endo cyclization, and triethylamine mediated Pd catalyzed 5-exo cyclization. Under optimized
Sulfoxide-mediated approach to flavones through one-pot Knoevenagel condensation/oxa-Michael addition/sulfoxide elimination process of β-(o-hydroxyaryl)-ketosulfone with arylaldehydes
gram-scale synthesis of flavones is described by a one-pot straightforward sulfoxide-mediated Knoevenagel condensation/intermolecular oxa-Michael annulation/sulfoxide elimination process of β-(o-hydroxyaryl)-ketosulfones (dual nucleophile) and arylaldehydes (dual electrophile). The expeditious synthetic route sets up flavones, including the bond formation of one CO and one double CC bonds via a formal (5 + 1)
在本文中,通过一锅法直接亚砜介导的 Knoevenagel 缩合/分子间 oxa-Michael 环化/β-(o-羟基芳基)-酮砜(双亲核试剂)和芳基醛(双亲电试剂)。快速合成路线建立了黄酮,包括通过形式 (5 + 1) 环加成形成一个 C O 键和一个双 C C 键。此外,其中,化合物70 亿可能是进一步开发药物以造福抗衰老领域的绝佳起点。
A novel one pot route to flavones under dual catalysis, an organo- and a Lewis acid catalyst
作者:Gourhari Maiti、Rajiv Karmakar、Rudraksha N. Bhattacharya、Utpal Kayal
DOI:10.1016/j.tetlet.2011.08.078
日期:2011.10
Substituted phenylacetylenes react with various o-hydroxy aromatic aldehydes under dual catalysis of piperidine and FeCl3 in refluxing toluene to yield flavones in good to excellent yield. Atmospheric oxygen acts as stoichiometric oxidant in the process. Some of these compounds had been recently reported to show fair insecticidal activity against Spodoptera frugiperda. (C) 2011 Elsevier Ltd. All rights reserved.
A two step synthesis of BzR/GABAergic active flavones via a Wacker-related oxidation
作者:Michael Lorenz、M. Shahjahan Kabir、James M. Cook
DOI:10.1016/j.tetlet.2009.12.107
日期:2010.2
A general route for the synthesis of biologically important flavones is reported via a two step sequence employing a catalytic Wacker-Cook oxidation(4b) as the key step. (C) 2009 Elsevier Ltd. All rights reserved.
Ghotekar; Mandhane; Joshi, Indian Journal of Heterocyclic Chemistry, 2010, vol. 19, # 4, p. 341 - 344