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61.
1‐(Cyclohexylamino)‐2‐(aryl)pyrrolo[1,2‐a]quinoline‐3‐carbonitrile derivatives were synthesized in an efficient method from four‐component condensation reaction between cyclohexyl isocyanide, quinoline, malononitrile, and aromatic aldehydes in the presence of a catalytic amount of titanium dioxide (TiO2) in CH2Cl2 at ambient temperature in good yields. Silica gel column chromatography was employed for HCN elimination and then 1, 3 hydrogen shift was led to form final products 5a , 5b , 5c , 5d , 5e .  相似文献   
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63.
2-Acetyl-3-(phenylamino)indolizine-1-carboxamide derivatives were obtained via a one-pot domino reaction of alkyl or aryl isocyanides and pyridine-2-carbaldehyde in the presence of acetoacetanilide in toluene without any prior activation or modification.  相似文献   
64.
An efficient and direct protocol is described for the preparation of α-amino phosphonates derivatives by employing a multi-component, one-pot condensation reaction of aldehyde, amine and trialkyl phosphite in the presence of silica-supported perchloric acid (3 mol%) under solvent-free conditions. The thermal solvent-free green procedure offers advantages such as shorter reaction time, simple work-up, high yield, recovery and reusability of catalyst.  相似文献   
65.
The reaction between dialkyl acetylenedicarboxylates and NH heterocyclic compounds in the presence of triethyl phosphite leads to stable phosphorus ylide derivatives in good yields. The X‐ray crystallographic data and theoretical study show that there is a resonance between two bonds of C19P1 and C191O191 in phosphorus ylide 4d . This compound crystallizes in the orthorhombic system, space group (Pca21), with unit cell parameters a = 17.3699(3) Å, b = 13.5500(2) Å, c = 18.4627(3) Å, α = 90°, β = 90°, γ = 90°, Z = 8, and V = 4345.4(12) Å3. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:715–722, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20739  相似文献   
66.
A simple and efficient one‐pot three‐component reaction between hexamethyl phosphorous triamide and dimethyl acetylenedicarboxylate (DMAD) in the presence of CH‐acids, such as acetylacetone, 1,3‐indandione, dibenzoylmethane, anthrone, and N,N‐dimethylbarbituric acid, has been studied. In all cases, new and stable phosphorus ylides are obtained in excellent yields. These stable ylides exist in solution as a mixture of two geometrical isomers as a result of restricted rotation around the carbon–carbon partial double bond, resulting from conjugation of the ylide moiety with the adjacent carbonyl group. From the reaction of N,N‐dimethylbarbituric acid with DMAD in the presence of hexamethyl phosphorous triamide, a 1,4‐diionic organophosphorus compound is obtained. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 24:84–89, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.21067  相似文献   
67.
In the present work, the catalytic activity of quinolinic acid (QUIN) was studied for the synthesis of spirochromene and pyranopyrazole derivatives from readily available materials. The salient features of these one‐pot multicomponent protocols are the clean reaction profile, easy isolation of products, no chromatographic separation techniques, high efficiency, short reaction time, and high yield of products plus using QUIN as a new, inexpensive, commercially available, and efficient organocatalyst.  相似文献   
68.
Research on Chemical Intermediates - The aim of this research is the synthesis of a novel acidic nanocatalyst using the layer-by-layer assembly technique. The CoFe2O4@TRIS@sulfated boric acid...  相似文献   
69.
In this study, three eco-friendly, efficient, and convenient protocols have been reported for one-pot synthesis of 2,4,6-triaryl pyridine, 2-amino-3-cyanopyridine, and polyhydroquinoline derivatives using salicylic acid as a catalyst under solvent-free condition. The reported protocols offer several significant advantages such as the application of a nontoxic, neutral, and cheap catalyst, environmentally friendly conditions, the easy isolation of products by filtering, short reaction times, simple methodology, and good yields.  相似文献   
70.
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