(E)-3-(芳氨基)-2-苯乙烯基喹唑啉-4(3 H)-硒的硒催化氧化C H胺:1,2-二芳基吡唑并[5,1- b ]喹唑啉的无金属合成-9(1 H)-个
摘要:
一种新颖的无金属催化方案,通过(E)-3-(芳基氨基)-的分子内氧化CH胺合成1,2-二芳基吡唑并[5,1- b ]喹唑啉-9(1 H)-ones。已经开发了2-苯乙烯基喹唑啉-4(3 H)-一,产率中等至良好。该方法显示出良好的官能团耐受性。提出的方法为2,3-稠合的喹唑啉酮的核心结构提供了一条新的合成途径。而且,本合成路线可以容易地按比例放大至克量而没有困难。可能的机制涉及硒离子,然后是三元环的开环以形成C–N键。
Domino synthesis of fused pyrazolo[5,1- b ]quinazolin-9(1 H )-ones catalyzed by CuI via subsequent Michael addition and elimination
作者:Yan Zhang、Jing Xu、Chao Li、Xiang-Shan Wang
DOI:10.1016/j.tet.2015.09.055
日期:2015.11
A Domino reaction of 2-aminobenzohydrazides and 2-bromocinnamaldehydes is treated in the presence of CuI and Cs2CO3, and gives unexpected pyrazolo[5,1-b]quinazolin-9(1H)-one derivatives in good yields. A possible mechanism containing subsequent Michael addition and elimination is proposed to explain the formation of the pyrazole ring. This new procedure has the advantages of one-pot, available reactant, and milder conditions. (C) 2015 Elsevier Ltd. All rights reserved.
Copper(I)-catalyzed synthesis of 1-arylpyrazolo[5,1-b]quinazolin-9(1H)-one via intramolecular alkyne hydroamination
作者:Dong-Sheng Chen、Mei-Mei Zhang、Yu-Ling Li、Yun Liu、Xiang-Shan Wang
DOI:10.1016/j.tet.2014.03.048
日期:2014.5
The 1-arylpyrazolo[5,1-b]quinazolin-9(1H)-one derivatives were obtained via intramolecular alkyne hydroamination reaction of 2-amino-N'-arylbenzohydrazide and alkynal diethyl acetal in the presence of CuBr and Cs2CO3. This new procedure provides an efficient method to construct fused tricyclic heterocycle containing both pyrazole and quinazoline analogues. (C) 2014 Elsevier Ltd. All rights reserved.