Synthesis of
4H
‐chromene‐isoxazole hybrids via
ortho
‐hydroxy directing cyclization of isoxazole‐styrenes and Michael addition of imino‐chromenes in aqueous medium
摘要:
AbstractA green, efficient, and one‐pot method synthesis of functionalized 4H‐chromene‐isoxazole hybrids is reported via o‐hydroxy group directing cyclization of isoxazole‐styrenes and Michael addition of 3,5‐dimethyl‐4‐nitroisoxazole on 2‐imino‐2H‐chromene‐3‐carbonitrile (independent methods). The developed methodology was further extended for nitromethane, malononitrile, and alkylcyanoacetates as Michael donors.
The reaction of salicylic aldehydes with malononitrile was reinvestigated, and the reaction pathway was followed by 1H NMR spectroscopy. A delicate control of the experimental conditions allowed the synthesis of 2-imino-2H-chromene-3-carbonitriles 1, (2-amino-3-cyano-4H-chromen-4-yl)malononitriles 2, 4-amino-5-imino-2,7-dimethoxy-5H-chromeno[3,4-c]pyridine-1-carbonitrile 12, and (4,5-diamino-1-cyano-1
重新研究了水杨醛与丙二腈的反应,并通过1 H NMR光谱追踪了反应路径。的实验条件微妙控制允许的2-亚氨基-2-合成ħ色烯-3-腈1,(2-氨基-3-氰基-4- ħ -苯并吡喃-4-基)丙二腈2,4-氨基5-亚氨基-2,7-二甲氧基-5- ħ -chromeno [3,4 ç ]吡啶-1-甲腈12,和(4,5-二氨基-1-氰基1,10b二氢-2 ħ -chromeno [3,4- c ]吡啶-2-亚基)丙二腈13。两个新颖的2-亚氨基二烯二聚体,分别具有结构8和9,被隔离和充分表征。化合物8a对曲霉属的活性。生长和曲霉毒素A的产生进行了评估。生物测定的结果表明,以2mM的浓度施用的化合物8a完全抑制了所测试的真菌的生长。赭曲霉毒素A的生产由曲霉alliaceus减少了约93%的与该化合物的200μM溶液。观察到对类似结构8b的中等抑制作用,并且未发现对用作二聚体8的合成前体的化合物2和1有抑制作用。
Visible light induced, catalyst free, convenient synthesis of chromene nucleus and its derivatives using water–ethanol mixture as a solvent
Eco-friendly, one pot synthesis of chromene and pyridine nucleus initiated by visible light.
环保的,一锅法合成由可见光引发的咔啉和吡啶核。
Electrocatalytic chain transformation of salicylaldehyde and CH acids into substituted 4H-chromenes
作者:S. K. Feducovich、M. N. Elinson、A. S. Dorofeev、S. V. Gorbunov、R. F. Nasybullin、N. O. Stepanov、G. I. Nikishin
DOI:10.1007/s11172-008-0093-9
日期:2008.3
Electrochemically initiated catalytic chain transformation of salicylaldehydes and CH acids containing the cyano group in an ethanolicsolution in an undivided cell produced substituted 4H-chromenes in 85–95% yields.
Aegle marmelos in heterocyclization: greener, highly efficient, one-pot three-component protocol for the synthesis of highly functionalized 4H-benzochromenes and 4H-chromenes
作者:Sachin Shinde、Shashikant Damate、Smita Morbale、Megha Patil、Suresh S. Patil
DOI:10.1039/c6ra28779d
日期:——
A facile, one-potthree-component protocol for the synthesis of 2-amino-4H-chromene derivatives has been demonstrated using Bael Fruit Extract (BFE) as a natural catalyst in a green reaction medium. This method offers a mild, efficient and highly economical protocol since the reaction proceeds in natural BFE-catalyst at room temperature under aerobic conditions with a very short reaction time (30 min)
An efficient condensation of substituted salicylaldehyde and malononitrile catalyzed by lipase under microwave irradiation
作者:Fengjuan Yang、Zhi Wang、Haoran Wang、Chunyu Wang、Lei Wang
DOI:10.1039/c5ra10565j
日期:——
The present work illustrates the condensation of substituted salicylaldehyde and malononitrile catalyzed by lipase under microwave irradiation. The reaction obtains two different products by a delicate control of the substrate molar ratio and reaction time. This protocol has the advantages of high yield, short reaction time and environmental friendliness.