Iodine-Catalyzed Regioselective Sulfenylation of 4H-Pyrido[1,2-a]pyrimidin-4-ones with Sulfonyl Hydrazides
作者:Shaohua Wang、Wenjie Liu、Zhihao Cai、Ziying Li、Jianwen Liu、Anda Wang
DOI:10.1055/s-0036-1588549
日期:2018.1
A simple and efficient method for direct sulfenylation of 4H-pyrido[1,2-a]pyrimidin-4-ones with sulfonyl hydrazides has been developed. The transformation is catalyzed by iodine under metal-free conditions with high regioselectivity and good functional-group tolerance.
Solvent-Free Synthesis of 4<i>H</i>-Pyrido[1,2-<i>a</i>]pyrimidin-4-ones Catalyzed by BiCl<sub>3</sub>: A Green Route to a Privileged Backbone
作者:Irwan I. Roslan、Qiu-Xuan Lim、Aijuan Han、Gaik-Khuan Chuah、Stephan Jaenicke
DOI:10.1002/ejoc.201500227
日期:2015.4
An extensive array of 4H-pyrido[1,2-a]pyrimidin-4-ones have been synthesized from commercially available 2-aminopyridines and β-oxo esters with excellent yields under solvent-free conditions. The reaction, catalyzed by cheap and nontoxic BiCl3, proceeds with short reaction times under mild conditions and normal atmosphere. Only water and alcohol are formed as co-products in this green reaction.
Enantioselective hydrogenation of annulated arenes: controlled formation of multiple stereocenters in adjacent rings
作者:Mario P. Wiesenfeldt、Daniel Moock、Daniel Paul、Frank Glorius
DOI:10.1039/d0sc07099h
日期:——
hydrogenation of annulated arenes using 4H-pyrido[1,2-a]pyrimidinones as substrates. The method selectively generates multiple stereocenters in adjacent rings leading to architecturally complex motifs, which resemble bioactive molecules. The mechanistic study of the stereochemical outcome revealed that the catalyst is able to overcome substrate stereocontrol providing all-cis-substituted products predominantly
我们报告了一种使用 4 H-吡啶并[1,2- a ]嘧啶酮作为底物对环状芳烃进行对映选择性氢化的方法。该方法选择性地在相邻环中生成多个立体中心,从而形成结构复杂的图案,类似于生物活性分子。立体化学结果的机理研究表明,该催化剂能够克服底物立体控制,主要提供全顺式取代的产物。在顺序方案中,实现了催化剂和底物立体控制之间的匹配相互作用,这有利于非对映和对映选择性获得反式产物。
Palladium-catalyzed direct alkenylation of 2-methyl-4H-pyrido[1,2-a]pyrimidin-4-ones using oxygen as the oxidant
A direct C-3 alkenylation of 2-methyl-4H-pyrido[1,2-a]pyrimidin-4-ones through palladium-catalyzed C–H activation usingoxygen as the terminal oxidant has been developed. This method provides an easy access to functionalized new 2-methyl-4H-pyrido[1,2-a]pyrimidin-4-one derivatives.
已经开发了通过使用氧作为末端氧化剂的钯催化的CH活化,可以使2-甲基-4 H-吡啶[1,2- a ]嘧啶-4-酮直接进行C-3烯基化反应。该方法提供了容易获得功能化的新的2-甲基-4 H-吡啶并[1,2 - a ]嘧啶-4-酮衍生物的方法。
[Bis(trifluoroacetoxy)iodo]benzene Mediated C‐3 Selenylation of Pyrido[1,2‐
<i>a</i>
]Pyrimidin‐4‐Ones Under Ambient Conditions
作者:Prasanjit Ghosh、Gautam Chhetri、Eliyahu Perl、Sajal Das
DOI:10.1002/adsc.202001426
日期:2021.4.13
[Bis(trifluoroacetoxy)iodo]benzene mediated C−H bond arylselenylation of 4H‐Pyrido‐[1,2‐a]‐Pyrimidin‐4‐ones using readily available organodiselenides. This methodology is scalable and permits for the generation of a broad spectrum of functionally and structurally diverse selenoether derivatives in very promising yields (up to 98%). Notably, this protocol proceeds at ambientconditions and in the absence of
本文中,我们报道了[Bis(三氟乙酰氧基)碘]苯介导的4 H-吡啶基-[1,2 - a ]-嘧啶-4-基的4 H-吡啶键芳基硒基化反应。这种方法学是可扩展的,并允许以非常有希望的产率(高达98%)产生功能上和结构上多样化的多种硒醚衍生物。值得注意的是,该方案在环境条件下并且在没有金属的情况下进行。还证明了该方法在轻松合成屁股取代的5 H-噻唑并吡啶[3,2 - a ]嘧啶-4-酮中的应用。