Hyperbranched epoxide‐amine adducts were synthesized by a one‐pot microwave (MW) assisted reaction. 4‐(2,3‐epoxypropyl‐1‐oxy)benzonitrile was hydrogenated using Pd/C under microwave conditions, forming the AB2 monomer 1‐aminomethyl‐4‐(2,3‐epoxypropyl‐1‐oxy)benzene. Depending on the reaction temperature this monomer immediately reacts to give hyperbranched epoxide‐amine adducts. Mass spectrometric investigations proved the formation of a homologous series of oligomers containing up to six repeating units. Due to the complexing properties of the poly(amino alcohol) moieties in the presence of Cu2+ ions, large aggregates were formed.
An efficient and facile synthesis of cyanopyridines via a one‐pot four‐component reaction of aromatic aldehydes, acetophenones, malononitrile, or 2‐aminoprop‐1‐ene‐1,1,3‐tricarbonitrile in presence of sodium alkoxide or ammonium acetate under both microwave and thermal reaction conditions was introduced. 相似文献
An effective route to hydantoins is described, based on the 2 : 1 : 1 addition of arylsulfonyl isocyanates, dialkyl acetylenedicarboxylates, and dialkyl trialkylsilyl phosphites. The resulting tetrasubstituted, stable hydantoins 4 / 4′ (Table) were obtained in excellent yields, and their structures were corroborated spectroscopically (IR, 1H‐, 13C‐, 31P‐NMR, EI‐MS) and by elemental analyses. A plausible mechanism for this type of cyclization is proposed (Scheme 2). 相似文献
A convenient one‐pot microwave‐assisted synthesis of Benzopyrano[2,3‐c]pyrazol‐3‐one derivatives was developed, where Knoevenagel condensation and hydrazinolysis reactions were continuously performed under microwave irradiation without separation and purification of the intermediates until the last cyclocondensation reaction except the substrates addition. The one‐pot procedure exhibited shorter reaction times and higher yields (25–55%) of the objects than the conventional heating method. 相似文献
A one‐pot and efficient synthesis of substituted N‐dichloroacetyl‐4,5‐dimethyl‐1,3‐oxazolidines utilizing the reaction of alkamine with aldehyde or ketone in refluxing benzene under microwave irradiation was described. The N‐acylation was followed with dichloroacetyl chloride and NaOH acting as the attaching acid agent. All compounds were characterized by IR, 1H NMR, 13C NMR, and element analysis. Additionally, the absolute configuration of 4a was determined by X‐ray crystallography. All the compounds were tested for their herbicide safeners activity of protecting the maize from the injury of acetochlor. 相似文献
An eco‐efficient one‐pot three component reaction for the synthesis of 3,5‐dispirosubstituted piperidines is reported by condensing of 2‐thiobarbituric acid, formaldehyde, and aromatic amines in the presence of a catalytic amount of p‐toluenesulfonic acid (1.0 equivalent) in dimethyl sulfoxide. The reactions were examined by two special methods such as classical heating and microwave (MW) irradiation. In general, improvements in rates and yields were observed when reactions were carried out under MW irradiation compared to the conventional method. 相似文献
Zinc and cadmium complexes of meso‐arylisoporphyrins carrying a pyrrolyl or dipyrrinyl substituent at the sp3 carbon atom were obtained through a simple one‐pot variation of the Alder–Longo porphyrin synthesis. Key to the formation and stabilization of isoporphyrins is the presence of metal acetates during the oxidative macrocyclization step. The characteristic Q‐bands of isoporphyrins are found in the NIR region between 750 nm and 880 nm. All of the isolated pyrrolyl‐ and dipyrrinyl‐appended isoporphyrins are stable under typical laboratory conditions and allow chemical transformations like BF2 coordination, transmetalation, and ligand exchange. 相似文献
A series of novel 1,3,5‐triarylpyrazoles 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h , 3i , 3j , 3k , 3l , 3m , 3n , 3o , 3p , 3q , 3r , 3s , 3t , 3u , 3v , 3w , 3x were synthesized from flavanones, arylhydrazines, and trimethyl phosphate in an one‐pot procedure. Facile reaction process, easy after‐reaction workshop, and good yields are the distinct characteristics of the developed protocol. The target compounds were characterized by element analysis, infrared ray (IR), 1H NMR spectra, and electrospray ionization‐mass spectrometry. The structure of representative compound 3h (C23H20N2O3, Mr = 372.42) was further confirmed by X‐ray diffraction. It crystallizes in monoclinic, space group P 21/c, a = 8.9720(5), b = 24.5523(13), c = 8.9687(6) Å, α = 90.0000, β = 102.6417(17), γ = 90.0000°, V = 1927.76(20) Å3, Z = 4, μ(MoKα) = 0.086, F(000) = 784, Dc = 1.283 g/cm3, the final R = 0.0349 and wR = 0.0844 for 1668 observed reflections (I > 2σ(I)) 相似文献
1,2,4‐Triazine compounds were synthesized via two coupled domino strategies employing simple and readily available arylacetaldehydes/arylethyl alcohols as starting materials. The reactions proceed smoothly in one pot with the advantages of high functional groups tolerance, being transition metal‐free, and employing environmentally friendly oxidants such as I2 and IBX , providing access to the desired 1,2,4‐triazine products in excellent yields. 相似文献
The synthesis of N‐substituted‐5‐arylidenerhodanines was carried out by the optimized one‐pot sequential four‐component procedure with the condensation between 4‐aminobenzenesulfonamide, suitable aldehyde, ethyl bromoacetate, and carbon disulfide. In addition to traditional method, microwave‐irradiated and ultrasound‐irradiated techniques were implemented in water at ambitious conditions, and the target compounds were obtained in high yields and purity without purification methods. The enzyme inhibition activity of newly synthesized compounds on carbonic anhydrase (II) was also evaluated. The reference inhibitor molecule was sulfanilamide, the IC50 value of which was 3.5 μM. It was also found that the IC50 values of all examined molecules were in nanomolar level and much smaller than those of sulfanilamide. The inhibition between 93.5 and 99.6% was observed in the presence of new compounds synthesized in the present study at the accessible maximum concentration in the reaction mixtures. 5j , among the tested compounds possessing the lowest IC50 value, was found to be the most potent carbonic anhydrase (II) inhibitor. 相似文献
The development of effective strategies for fabrication of fluorescent organic nanoparticles (FONs) with an aggregation‐induced emission (AIE) feature has an important impact on the biomedical applications of these AIE‐active FONs. In the current work, an ultrafast strategy for fabricating AIE‐active FONs is developed through a “one‐pot” microwave‐assisted, catalysts‐free, and solvent‐free Kabachnik–Fields (KF) reaction for the first time. It is demonstrated that such organophosphorous‐containing AIE‐active block polymers can be synthesized within 2 min under air atmosphere through the microwave‐assisted KF reaction. These polymers show amphiphilic properties and can self‐assemble into mPEG‐CHO‐Phe‐NH2‐DEP FONs, which display high water dispersibility and desirable optical properties. Biological evaluation results suggest that the mPEG‐CHO‐Phe‐NH2‐DEP FONs exhibit low toxicity and are potential for biological imaging applications. More importantly, many other multifunctional AIE‐active FONs can also be fabricated through the strategy described in this work owing to the universality of KF reaction. Besides, combined with the excellent properties of mPEG‐CHO‐Phe‐NH2‐DEP FONs, it is believed that such microwave‐assisted KF reaction shall be an effective route for designing various AIE‐active nanomaterials for different biomedical applications.
A versatile synthesis of 3‐cyano‐2‐pyridones via a one‐pot, four‐component condensation of ethyl cyanoacetate, ketones, aldehydes, and ammonium acetate under very mild conditions has been developed. This method provides rapid access to this type of valuable heterocyclic compounds from readily available materials in a single operation. 相似文献
A scalable, one‐pot, enantioselective catalytic synthesis of 2‐pyrazolines from beta‐substituted enones and hydrazines is described. Pivoting on a two‐stage catalytic Michael addition/condensation strategy, the use of an aldehyde to generate a suitable hydrazone derivative of the hydrazine was found to be key for curtailing background reactivity and tuning the catalyst‐controlled enantioselectivity. The new synthetic method is easy to perform, uses a new and readily prepared cinchona‐derived bifunctional catalyst, is broad in scope, and tolerates a range of functionalities with high enantioselectivity (up to >99:1 e.r.). The significant scalability of this methodology was demonstrated with the synthesis of more than 80 grams of a pyrazoline product with 89 % catalyst recovery. 相似文献
An efficient method for the synthesis of polysubstituted indolizines has been developed based on formal [4+2] annulation of 1‐acetylaryl 2‐formylpyrroles with enals, followed by oxidative aromatization. Pyridine‐type six‐membered rings were constructed in this transformation. This transition metal‐free reaction features mild reaction conditions, a broad substrate scope, and excellent functional group tolerance. Notably, the formyl group is well tolerated under reaction conditions. 相似文献
An efficient and rapid, solvent‐free, microwave‐accelerated, one‐pot, three‐component protocol for thiazolidin‐4‐ones synthesis from organic azides has been reported for the first time via Staudinger/aza‐Wittig reaction. The microwave‐accelerated, solvent‐free approach overcomes the limitations associated with the prevailing solution phase methodologies. In particular, its novelty is that it eradicates the vital limitation, that is, accumulation of water (byproduct) that is known to affect the yield and rate of the reaction. Thus, a library of thiazolidin‐4‐ones has been synthesized in short time in excellent yields (92–96%). 相似文献
A one‐pot method for the synthesis of 3‐amino‐7‐nitro‐1,2‐dihydroisoquinoline‐4‐carbonitriles from 2‐chloro‐5‐nitrobenzylamines and malononitrile has been developed. 相似文献