Synthesis of Substituted Azaindenes: Synthesis of New Pyrazolo[1,5-<i>a</i>]pyrimidine Derivatives
作者:Mohamed Hilmy Elnagdi、Ayman Wahba Erian
DOI:10.1246/bcsj.63.1854
日期:1990.6
Severalnew pyrazolo[1,5-a]pyrimidines were synthesized via the reaction of 4,5-disubstituted 3-aminopyrazoles 1a–d with 3-dimethylaminopropiophenone, cinnamaldehyde, benzylideneacetophenone and tetracyanoethylene.
An efficient and facile protocol has been developed for the synthesis of pyrazolo[1,5-a]pyrimidines through the tandem reaction of 3-aminopyrazoles and chalcones in the presence of catalytic amounts of KOH. The reported method offers access to 5,7-diarylpyrazolo[1,5-a]pyrimidines in good to excellent yields. A gram-scale reaction has been performed to demonstrate the potency of optimized procedure for
在催化量的KOH存在下,通过3-氨基吡唑和查耳酮的串联反应合成吡唑并[1,5- a ]嘧啶的有效而简便的方法已被开发出来。报道的方法提供了以良好或优异的产率获得5,7-二芳基吡唑并[1,5- a ]嘧啶的方法。已经进行了克规模的反应,以证明用于放大工艺的优化程序的效力。
Carbon–Carbon Bond Cleavage Reaction: Synthesis of Multisubstituted Pyrazolo[1,5-<i>a</i>]pyrimidines
作者:Pallabi Saikia、Sanjib Gogoi、Romesh C Boruah
DOI:10.1021/acs.joc.5b00933
日期:2015.7.2
A newcarbon–carbonbond cleavage reaction was developed for the efficientsynthesis of multisubstituted pyrazolo[1,5-a]pyrimidines. This base induced reaction of 1,3,5-trisubstituted pentane-1,5-diones and substituted pyrazoles afforded good yields of the pyrazolo[1,5-a]pyrimidines.
为了有效合成多取代的吡唑并[1,5- a ]嘧啶,开发了一种新的碳-碳键裂解反应。该碱诱导的1,3,5-三取代戊烷-1,5-二酮与取代的吡唑的反应提供了吡唑并[1,5- a ]嘧啶的良好收率。
Visible-Light-Mediated Regioselective C3–H Selenylation of Pyrazolo[1,5-<i>a</i>]pyrimidines Using Erythrosine B as Photocatalyst
作者:Tathagata Choudhuri、Suvam Paul、Sourav Das、Devendra Deo Pathak、Avik Kumar Bagdi
DOI:10.1021/acs.joc.3c00720
日期:2023.7.7
visible-light-induced efficient methodology has been developed for the C–H selenylation of pyrazolo[1,5-a]pyrimidine derivatives employing erythrosine B as the photocatalyst. This is the first report on the regioselective selenylation of pyrazolo[1,5-a]pyrimidines. The efficiency of this methodology for the selenylation of different electron-rich heterocycles like pyrazole, indole, imidazo[1,2-a]pyridine, imidazo[2,1-b]thiazole
采用赤藓红 B 作为光催化剂,开发了一种可见光诱导的吡唑并[1,5- a ]嘧啶衍生物C-H 硒化的有效方法。这是关于吡唑并[1,5- a ]嘧啶区域选择性硒化的第一份报告。该方法对不同富电子杂环(如吡唑、吲哚、咪唑并[1,2- a ]吡啶、咪唑并[2,1- b ]噻唑和4-(苯氨基)-2 H)的硒化效率-chromen-2-one 也已得到证实。探索赤藓红B作为光催化剂的过程简单温和、底物范围广、实用性强以及使用环保的能源、氧化剂和溶剂是该方法的吸引人的特点。
Pyrazolo[1,5‐
<i>a</i>
]pyrimidine‐Dioxaborinine Hybrid Dyes: Synthesis and Substituent Effect in the Photophysical Properties
A novel family of hybrid fluorophores based on the pyrazolo[1,5-a]pyrimidine-dioxaborinine (PP-DB) system is provided by constructing the dioxaborinine moiety on the fused ring in a one-pot manner.
通过以一锅法在稠合环上构建二氧杂硼啉部分,提供了基于吡唑并[1,5- a ]嘧啶-二氧杂硼啉 (PP-DB) 系统的新型杂化荧光团家族。