制备了芳hydr并使其与吡唑基亚甲基丙二腈衍生物反应,生成在C-5处被吡唑衍生物取代的2,5-二氢哒嗪。通过在邻位使用含有氰基的氮杂胺,可以形成缩合的哒嗪并[1,6- a ]喹唑啉衍生物。合成的哒嗪的后续乙酰化导致嘧啶[4,5– c ]哒嗪化合物的形成,可以将其视为4-脱氮杂黄酮衍生物。所有新化合物均通过不同的光谱工具进行了全面表征,并使用2D-HMBC光谱对2,5-二氢哒嗪进行了结构明确的鉴定
Thiourea is an inexpensive, efficient and mild catalyst for the synthesis of Knoevenagelcondensation of pyrozoles derivate. In the presence of 10 mol% of thiourea, pyrazole aldehyde react with active methylene compound under microwave‐assisted solvent‐free conditions at 300 W for 2‐5 min to give corresponding products in good yields.
A green and efficient methodology has been developed for the construction of 2-[(1,3-diaryl-4-pyrazolyl)methylene]malononitriles, potent antioxidant molecules, in good to excellent yields in five minutes from 1,3-diarylpyrazole-4-carbaldehydes and malononitrile using PEG-400 and water at ambient temperature under catalyst-free conditions. The PEG-400 could be reused without appreciable loss in the yield. The methodology has been extended to the synthesis of a diverse range of homo/heteroaryl-based nitriles and acrylates, reflecting its versatility.
Straightforward syntheses of nitriles, acrylates, and acrylamides in aqueous propan-1,2-diol: a catalyst free and waste free methodology
A mild, elegant, catalyst free, and waste free methodology has been developed for the clear-cut synthesis of a diverse range of nitriles, acrylates, and acrylamides in good to excellent yields using aqueous propan-1,2-diol, a green reaction medium, at ambient temperature. Operational simplicity and recyclability of the reaction medium are added advantages of the methodology. (C) 2015 Elsevier Ltd. All rights reserved.
Facile Synthesis of 3-Amino-2,5-dihydropyridazines and 4-Deazatoxoflavin Analogues via [3 + 3] Atom Combination: Approaches to Pyridazine Incorporating Pyrazole Moiety
作者:Amr M. Abdelmoniem、Said A. S. Ghozlan、Holger Butenschön、Ismail A. Abdelhamid
DOI:10.1002/jhet.2606
日期:2017.1
Arylhydrazones are prepared and reacted with pyrazolylmethylene malononitrile derivatives yielding 2,5‐dihydropyridazines substituted at C‐5 by pyrazole derivatives. Utilizing azaenamine containing a cyano group at the ortho position enabled the formation of the condensed pyridazino[1,6‐a]quinazoline derivatives. A subsequent acetylation of the synthesized pyridazines led to the formation of pyrimido[4
制备了芳hydr并使其与吡唑基亚甲基丙二腈衍生物反应,生成在C-5处被吡唑衍生物取代的2,5-二氢哒嗪。通过在邻位使用含有氰基的氮杂胺,可以形成缩合的哒嗪并[1,6- a ]喹唑啉衍生物。合成的哒嗪的后续乙酰化导致嘧啶[4,5– c ]哒嗪化合物的形成,可以将其视为4-脱氮杂黄酮衍生物。所有新化合物均通过不同的光谱工具进行了全面表征,并使用2D-HMBC光谱对2,5-二氢哒嗪进行了结构明确的鉴定