Intramolecular Heck Reaction on Bromobenzyloxy-Substituted Chromenes: Formation of Chelated Ketones
摘要:
Heck reaction on 2-bromobenzyloxy-substituted 4H-chromene derivatives using Pd(OAc)(2) in Aliquat 336 and N,N-dimethylformamide mixture leads to intramolecular heteroannulation along with hydrolysis, affording chelated 6H-benzo[c]chromen-2-yl ketones. The method offers Pd(0)-catalysis and regioselectivity in product formation. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications (R) to view the free supplemental file.
Synthesis and in vitro microbiological evaluation of novel series of 8-hydroxy-2-(2-oxo-2H-chromen-3-yl)-5-phenyl-3H-chromeno [2,3-d]pyrimidin-4(5H)-one derivatives catalyzed by reusable silica-bonded N-propylpiperazine sulfamic acid
作者:M. Ghashang、S. Sheik Mansoor、K. Aswin
DOI:10.1007/s11164-013-1419-2
日期:2015.5
Silica-bonded propylpiperazine- N -sulfamic acid is employed as a recyclable catalyst for the synthesis of a series of 8-hydroxy-2-(2-oxo-2 H -chromen-3-yl)-5-phenyl-3 H -chromeno[2,3- d ]pyrimidin-4(5 H )-one derivatives by the condensation of 2-amino-3-cyano-7-hydroxy-4-phenyl-4 H chromene derivatives with coumarin-3-carboxylic acid. The heterogeneous catalyst was used for four runs. This method
二氧化硅键合propylpiperazine- ñ -氨基磺酸被用作一系列的8-羟基-2-(2-氧代- 2的合成一个可回收催化剂 ħ -苯并吡喃-3-基)-5-苯基-3- ħ - chromeno [2,3 - d ]嘧啶-4(5 H )-衍生物,是通过2-氨基-3-氰基-7-羟基-4-苯基-4 H 色烯衍生物与香豆素-3-羧酸的缩合而得到的。非均相催化剂用于四次运行。该方法具有收率高,反应更清洁,方法简单,反应时间短,后处理容易的优点。评价所有化合物对不同细菌和真菌菌株的体外抗菌活性。
Green protocol for synthesis of MgFe2O4 nanoparticles and study of their activity as an efficient catalyst for the synthesis of chromene and pyran derivatives under ultrasound irradiation
procedure to synthesize 2-amino-7-hydroxy-4H-chromene and tetrahydrobenzo[b]pyran derivatives was established through the chemical reaction between different aldehydes, malononitrile and resorcinol (or dimedone) in the presence of MgFe2O4 nanoparticles as a beneficial catalyst in ethanol as solvent underultrasoundirradiation. Moreover, the synthesized MgFe2O4 nanoparticles were easily recovered by an
在这项研究中,MgFe 2 O 4纳米颗粒是通过绿色和简单的方法合成的。然后在MgFe 2 O 4存在下,通过不同醛,丙二腈和间苯二酚(或二甲酮)之间的化学反应,建立了合成2-氨基-7-羟基-4 H-色烯和四氢苯并[ b ]吡喃衍生物的有效方法。超声辐照下,纳米颗粒作为有益的催化剂,以乙醇为溶剂。此外,合成的MgFe 2 O 4纳米粒子很容易通过外部磁体回收,并重复使用了四次,而不会显着降低其催化活性。简单,快速,有效,生态友好以及快速纯化方法以及高产物收率是本化学反应的一些优点。
Heterogenization of an imidazolium ionic liquid based on magnetic carbon nanotubes as a novel organocatalyst for the synthesis of 2-amino-chromenes via a microwave-assisted multicomponent strategy
作者:Zohre Zarnegar、Javad Safari
DOI:10.1039/c6nj01631f
日期:——
ysilylpropyl)-1H-imidazol-3-ium chloride. This nanocomposite was found to be an efficient organocatalyst for the synthesis of 2-amino-chromenes via a microwave-assisted multicomponentstrategy in aqueous media. The attractive features of this simple method include easy isolation of products, milder and cleaner reaction conditions, higher yields and purity of the product and an easier work-up procedure
合成了咪唑鎓离子液体功能化的磁性多壁碳纳米管(CNTs–Fe 3 O 4 –IL),并使用FT-IR,VSM,SEM,TEM,XRD,TGA等不同的表征技术研究了纳米复合材料的结构,形态和性能。和DTA。为了合成CNT-Fe 3 O 4 -IL,用1-甲基-3-(3-三甲氧基甲硅烷基丙基)-1 H-咪唑-3-氯化铵对碳纳米管上负载的磁铁矿(CNT-Fe 3 O 4)进行了改性。此纳米复合材料被认为是为2-氨基-色烯合成的高效有机催化剂通过水性介质中的微波辅助多组分策略。这种简单方法的吸引人的特点包括:易于分离产物,较温和,更清洁的反应条件,较高的产率和纯度的产物以及较简便的后处理程序。只需施加外部磁场即可轻松分离出这种非均相催化剂,并且可循环使用的有机催化剂可以重复使用几次,而不会造成任何明显的活性损失。离子液体和磁性固体载体纳米材料的优点的结合提供了进行催化过程的环境友好的程序。
Application of {[4,4′-BPyH][C(CN)3]2} as a Bifunctional Nanostructured Molten Salt Catalyst for the Preparation of 2-Amino-4H-chromene Derivatives under Solvent-Free and Benign Conditions
作者:Mohammad Zolfigol、Meysam Yarie、Saeed Baghery
DOI:10.1055/s-0035-1561345
日期:——
The bifunctionalnanostructured molten salt [4,4′-bipyridine]-1,1′-diium tricyanomethanide has been employed as a highly efficient and powerful catalyst for the preparation of 2-amino-4H-chromenes. A wide variety of aromatic aldehydes was condensed with malononitrile and resorcinol, 1-naphthol or 2-naphthol under mild and solvent-free conditions. This protocol has the advantages of short reaction times
The amino side chains do matter: chemoselectivity in the one-pot three-component synthesis of 2-amino-4H-chromenes by supramolecular catalysis with amino-appended β-cyclodextrins (ACDs) in water
作者:Yufeng Ren、Bo Yang、Xiali Liao
DOI:10.1039/c5cy01888a
日期:——
In this study, the one-pot three-component synthesis of 2-amino-4H-chromenes was accomplished by supramolecular catalysis using a series of well-designed amino-appended β-cyclodextrins (ACDs) in water. The catalytic mechanism was elucidated in detail with 1D and 2DNMR and ESI-MS analyses, while the key roles of amino side chains of ACDs in the reaction chemoselectivity were addressed for the first