聚(4-乙烯基吡啶)硫酸氢盐: 一个新的高效催化剂用于无溶剂条件下合成13-芳香基-茚并 [1,2-b] 石脑油 [1,2-e] 吡喃-12(13H)-酮（英文）

An facile and efficient protocol for the synthesis of 13‐aryl‐indeno[1,2‐b]naphtha[1,2‐e]pyran‐ 12(13H)‐ ones has been developed that proceeds via the one‐pot three‐component sequential reaction of an aromatic aldehyde with β‐naphthol and 2H‐indene‐1,3‐dione under solvent‐free conditions in the presence of a poly(4‐vinylpyridinium)hydrogen sulfate(P(4‐VPH)HSO4) catalyst. The catalyst can be reused several times, making this procedure facile, practical, and sustainable. The simple experimental procedure, solvent‐free reaction conditions, use of an inexpensive catalyst, short react time, and excellent yields are some of the major advantages of this methodology.     

硅胶键合N-丙基哌嗪n-丙酸钠作为可循环使用催化剂催化4H-吡喃衍生物合成(英文)

Silica‐bonded N‐propylpiperazine sodium n‐propionate(SBPPSP) was found to act as an efficient solid base for the preparation of a series of 4H‐benzo[b]pyran derivatives. SBPPSP was used as a recyclable heterogeneous solid base catalyst for the synthesis of 3,4‐dihydropyrano[c]chromenes, 2‐amino‐4H‐pyrans, 1,4‐dihydropyrano[2,3‐c]pyrazoles, and 2‐amino‐4H‐benzo[e]‐chromenes via the condensation reaction of dimedone, ethyl acetoacetate, 3‐methyl‐1‐phenyl‐1H‐pyrazol‐5(4H)‐ one, and α‐naphthol, respectively, with aromatic aldehydes and malononitrile in refluxing aqueous ethanol. The heterogeneous solid base showed similar efficiency when reused in consecutive reactions.     

无溶剂条件下碳基固体酸催化一锅法合成酰胺烷基萘酚(英文)

An efficient, environmentally friendly procedure for the synthesis of amidoalkyl naphthols through the one‐pot, three‐component reaction of β‐naphthol, aryl aldehydes, and acetamide in the presence of a carbon‐based solid acid under thermal solvent‐free conditions is described. The beneficial fea-tures of this new synthetic approach include short reaction time, high yields, clean reaction profiles, and a simple work‐up procedure. Furthermore, the catalyst can be readily recycled and reused four times without obvious significant loss of activity. The structure of the catalyst was confirmed by Fourier transform infrared spectroscopy, N2 adsorption/desorption analysis, and X‐ray diffraction.     

Keplerate巨型纳米多孔聚氧钼酸盐作为可重复使用催化剂用于合成1,2,4,5-四取代咪唑(英文)

The Keplerate‐type giant nanoporous isopolyoxomolybdate (NH4)42[MoVI72MoV60O372‐(CH3COO)30(H2O)72], denoted {Mo132}, has been used as a catalyst for the synthesis of1,2,4,5‐tetrasubstituted imidazoles by the one‐pot, four‐component thermal reaction of benzil with aromatic aldehydes, primary amines, and ammonium acetate under solvent‐free conditions. The catalyst was prepared according to a previously published literature procedure using inexpensive and readily available starting materials, and subsequently characterized by FT‐IR, UV and X‐ray diffraction spectroscopy, as well as microanalysis. The results showed that {Mo132} exhibited high catalytic activity towards the synthesis of 1,2,4,5‐tetrasubstituted imidazoles, with the desired products being formed in good to high yields. Furthermore, the catalyst was recyclable and could be reused at least three times without any discernible loss in its catalytic activity. Overall, this new catalytic method for the synthesis of 1,2,4,5‐tetrasubstituted imidazoles provides rapid access to the desired compounds following a simple work‐up procedure, and avoids the use of harmful organic solvents. This method therefore represents a significant improvement over the methods currently available for the synthesis of tetrasubstituted imidazoles.     

二氧化硫脲:一锅合成吡喃并[4,3-b] 吡喃类化合物的高效可重复使用有机催化剂（英文）

A series of pyrano[4,3‐b]pyran derivatives have been synthesized in excellent yields by the reaction of aromatic aldehydes with malononitrile or cyanoacetate and 4‐hydroxy‐6‐methylpyran‐2‐one in water at 80 °C, with the transformation being catalyzed by an aqueous solution of thiourea dioxide(TUD). Upon completion of the reaction, the product was isolated by filtration or extraction and the remaining aqueous TUD solution could be reused several times without any discernible impact on its catalytic activity. This procedure offers several advantages over existing procedures, including high yields, operational simplicity, the use of a non‐toxic catalyst and solvent, short reaction time and minimum pollution of the environment, making it a useful and attractive process for the preparation of pyrano[4,3‐b]pyran derivatives.     

液-固相体系中以聚(N-乙烯基咪唑)为非均相碱性催化剂在超声波照射和无溶剂条件下催化不同醛和酮羟醛缩合(英文)

An ultrasound‐assisted aldol condensation reaction has been developed for a range of ketones with a variety of aromatic aldehydes using poly(N‐vinylimidazole) as a solid base catalyst in a liquid‐solid system. The catalyst can be recovered by simple filtration and reused at least 10 times without any significant reduction in its activity. The reaction is also amenable to the large scale, making the procedure potentially useful for industrial applications.     

Keplerate巨型纳米多孔聚氧钼酸盐作为可重复使用催化剂用于合成1,2,4,5-四取代咪唑(英文)

The Keplerate‐type giant nanoporous isopolyoxomolybdate (NH4)42[MoVI72MoV60O372‐(CH3COO)30(H2O)72], denoted {Mo132}, has been used as a catalyst for the synthesis of1,2,4,5‐tetrasubstituted imidazoles by the one‐pot, four‐component thermal reaction of benzil with aromatic aldehydes, primary amines, and ammonium acetate under solvent‐free conditions. The catalyst was prepared according to a previously published literature procedure using inexpensive and readily available starting materials, and subsequently characterized by FT‐IR, UV and X‐ray diffraction spectroscopy, as well as microanalysis. The results showed that {Mo132} exhibited high catalytic activity towards the synthesis of 1,2,4,5‐tetrasubstituted imidazoles, with the desired products being formed in good to high yields. Furthermore, the catalyst was recyclable and could be reused at least three times without any discernible loss in its catalytic activity. Overall, this new catalytic method for the synthesis of 1,2,4,5‐tetrasubstituted imidazoles provides rapid access to the desired compounds following a simple work‐up procedure, and avoids the use of harmful organic solvents. This method therefore represents a significant improvement over the methods currently available for the synthesis of tetrasubstituted imidazoles.     

原位生成的Ph_3C~+均相有机催化剂催化4,4'-芳亚甲基-二(3-甲基-1-苯基-1H-吡唑-5-醇)高效合成（英文）

Trityl chloride(Ph3CCl) efficiently catalyzes the condensation of 3‐methyl‐1‐phenyl‐1H‐pyrazol‐ 5(4H)‐one and aromatic aldehydes under mild and solvent‐free conditions, affording 4,4'‐(arylmethylene)‐ bis(3‐methyl‐1‐phenyl‐1H‐ pyrazol‐5‐ol)s in high to excellent yields and in short reaction time. The presence of the requisite organocatalytic trityl carbocation(Ph3C+) species was confirmed by analysis of infrared, 1H NMR, and ultra violet spectral data. A plausible mechanism was proposed for the reaction based on the observations and literature precedent.     

Fe_3O_4纳米粒子作为高效、可重复使用催化剂用于无溶剂条件下合成9,9-二甲基-9,10-二氢-8H-苯并[α]占吨11(12H)-酮（英文）

A simple and efficient method for the synthesis of 9,9‐dimethyl‐9,10‐dihydro‐8H‐benzo‐[α]xanthen‐11(12)‐one derivatives (DDBXs) was developed by the condensation reaction of various substituted aryl aldehydes with 2‐naphthol and dimedone using Fe3O4 magnetic nanoparticles (MNPs) as a heterogeneous catalyst under solvent‐free conditions at 90–110 °C.The experimental procedure is very simple,the products are formed in high yields and the catalyst is easily separated by applying an external magnetic field.     

Cu(II)salen配合物催化三组分偶联反应合成炔丙胺(英文)

A one pot three‐component coupling reaction of phenylacetylene, aldehyde, and amine derivatives in the presence of Cu(II) Salen complex as an efficient heterogeneous catalyst under solvent‐free conditions is reported. The catalyst displayed high activity and afforded the corresponding propargylamines in good to excellent yields. This method provides a wide range of substrate applicability. The catalyst was reused several times without significant loss of its catalytic activity.     

Recyclable zinc (II) ionic liquid catalyzed synthesis of azides by direct azidation of alcohols using trimethylsilylazide at room temperature

A new efficient method has been reported for the synthesis of azides by direct azidation of alcohols with TMSN₃ in presence of recyclable task specific ionic liquid (TSIL) [bmim]ZnCl₃ as a catalyst in DCM at room temperature. Ionic liquid [bmim]ZnCl₃ was synthesized under solvent free conditions and characterized by IR, ¹H NMR, ¹³C NMR and HRMS. The Lewis acidity of catalyst was also examined using IR spectroscopy. The main features of this new methodology are high yields of products, recyclability of catalyst, scalability of reaction to gram scale and short reaction time.     

Synthesis of Novel Greener Functionalized Ionic Liquids Containing Appended Hydroxyl

Novel “greener” functionalized ionic liquids have been prepared by the reaction of 1,2‐epoxy propane and dilute sulfuric acid with [EMIm]Br or [BMIm]Br formed by alkyl bromide (RBr) and 1‐methylimidazole. This kind of ionic liquid could be possibly used as green solvent and catalyst, especially as phase‐transfer catalyst in organic chemistry (e.g., the synthesis of ethoxybenzene). Their chemical structures were characterized by ¹H NMR, ¹³C NMR, and IR.     

Titanium-catalyzed [6π+2π]-cycloaddition of Si-containing alkynes to bis(1,3,5-cycloheptatriene-7-yl)alkanes

The reaction between Si-containing alkynes and bis(1,3,5-cycloheptatriene-7-yl)alkanes in the presence of the two-component catalyst Ti(acac)₂Cl₂-Et₂AlCl, led to the selective formation of mono- and bis-adducts – {9-[4-(2,4,6-cycloheptatrienyl)alkyl]-8-alkyl(phenyl)bicyclo[4.2.1]nona-2,4,7-triene-7-yl}(trimethyl)silanes and bis(7-trimethylsilyl-8-alkyl(phenyl)bicyclo[4.2.1]nona-2,4,7-triene-7-yl)alkanes in 78–86% yield. The structures of the obtained cycloadducts were confirmed by ¹H and ¹³C NMR spectroscopy.     

Preparation of Calix[4]arene Alkylamine Derivatives by Mannich Reaction and use as Phase-Transfer Catalysts for Esterification Reaction

In this study, 5,11,17,23-tetrakis[(N-ethylpiperazine)methyl]-25,26,27,28-tetrahydroxycalix[4]arene (3) and 5,11,17,23-tetrakis[(4-carboethoxy-N-piperidino) methyl]-25,26,27,28-tetrahydroxycalix[4]arene (4) were synthesized in one step according to the Mannich reaction by the treatment of calix[4]arene with a secondary amine (N-ethylpiperazine, ethyl-4-piperidincarboxylate) and formaldehyde. The calix[4]arene derivatives (3, 4) were characterized by a combination of FTIR, ¹H NMR and elemental analyses. The synthesized compounds were used in an esterification reaction as the phase transfer catalyst. The catalytic efficiency of the calix[4]arenes 3 and 4 was evaluated by carrying out the ester-forming reaction of alkali metal carboxylates (sodium butyrate or sodium caprylate) with p-nitrobenzyl bromide. It was observed that the ester-forming reaction of alkali metal carboxylates with p-nitrobenzyl bromide, using calix[4]arene-based catalyst 3 as a phase-transfer catalyst in dichloromethan, provided the best yields.     

Methoxycarbonylation of olefins catalyzed by palladium(II) complexes containing naphthyl(diphenyl)phosphine ligands

Palladium(II) complexes containing phosphine donor ligands derived from naphthyl(diphenyl)phosphine were synthesized and characterized by NMR and elemental analysis. The complexes were studied as catalyst precursors in the methoxycarbonylation reaction of several aromatic and aliphatic olefins under mild conditions. The catalysts reported high chemoselectivities (over 96%) and regioselectivities between 44% and 93% for different olefins. The best results were obtained over a styrene substrate with 97% of conversion after 6 h of reaction, with high regioselectivity (93%). Kinetic studies permitted the determination of the rate law (v = k [substrate]^1.21±0.02 [catalyst]^0.94±0.11 [acid]^0.52±0.03 [MeOH]^0.53±0.05 [CO]^0.65±0.03) for methoxycarbonylation of styrene. Copyright © 2014 John Wiley & Sons, Ltd.     

Synthesis and Reaction of Novel Spiro Pyrimidine Derivatives

2‐Mercapto‐6‐[(pyridin‐4‐ylmethylene)‐amino]‐3H‐pyrimidin‐4‐one 1 was synthesized from Schiff base reaction of 6‐amino‐2‐thiouracil with isonicotinaldehyde. The reaction of 1 with hydrazonyl chloride 2a , 2b , 2c , 2d afforded the novel pyrimidin‐4‐one 3a , 3b , 3c , 3d . Compounds 3a , 3b , 3c , 3d reacted with methyl iodide to give 4a , 4b , 4c , 4d . Subsequently, reaction of 4a , 4b , 4c , 4d with triethylamine as a catalyst in dry chloroform yielded tetraaza‐spiro[4.5]deca‐2, 8‐dien‐7‐one 5a , 5b , 5c , 5d . In addition, reaction of 1 with acrylonitrile gave pyrimidin‐propionitrile 6 . The cyclization of 6 by reacting with sodium ethoxide to give pyrimido [2, 1‐b] [1,3] thiazin‐6‐one 7 . The refluxing of 1 with bromine in acetic acid yielded 2‐bromo‐pyrimidin‐4‐one 8 . The latter compound 8 reacted with sodium azide gave tetrazolo‐pyrimidine 10 . The chemical structures of the newly synthesized compounds were characterized by IR, ¹H NMR, ¹³C NMR, and mass spectral analysis.     

Ultrasound mediated green synthesis of pyrano[2,3-c]pyrazoles by using Mn doped ZrO2

Mn doped zirconia is utilized as an environmental-friendly and efficient catalyst for an ultrasound mediated four-component coupling reaction, containing dimethylacetylenedicarboxylate/ethyl acetoacetate, hydrazine hydrate, malononitrile, and aromatic aldehyde. These reactions were performed under green solvent conditions, to yield pyrano[2,3-c]pyrazole-3-carboxylate/pyrano[2,3-c]pyrazole-5-carbonitrile derivatives (5a–g and 7a–g) with good to excellent yields (88–98%). The structures of the compounds were identified and confirmed by ¹H NMR, ¹⁵N NMR, ¹³C NMR, FT-IR and HR-MS spectral data. The prepared catalyst Mn/ZrO₂ was synthesized and fully characterized by various techniques including P-XRD, BET, SEM and TEM analysis. The main benefits of this process are short reaction times, easy work-up, reusability of the catalyst and no chromatographic purifications.     

离子液体[TEAPS]HSO_4催化“一锅法”合成2-取代-1H-菲并[9,10-d]咪唑

在室温离子液体3-(三乙胺基)丙磺酸硫酸氢盐([TEAPS]HSO4)的催化作用下,由菲醌、醋酸铵和芳香醛"一锅法"合成了一系列2-取代-1H-菲并[9,10-d]咪唑化合物.实验中考察了投料比、催化剂用量、溶剂、反应时间对反应的影响,确定了最优反应条件,给出了可能的反应机理.此外催化剂可以方便的回收,且循环使用四次其催化活性并没有显著降低.目标产物经过了1HNMR,13CNMR,IR和MS确证表征.条件温和,反应时间短,产率高,且对环境友好.     

A Simple One‐Pot Synthesis of Fully Substituted 1H‐Pyridone[1,2‐a]‐Fused‐1,3‐Diazaheterocycles

An efficient procedure for the synthesis of 7‐(aryl)‐8‐nitro‐2,3,6,7‐tetrahydroimidazo[1,2‐a]pyridinones, 8‐(aryl)‐9‐nitro‐3,4,7,8‐tetrahydropyridone[1,2‐a]pyrimidines and 9‐(aryl)‐10‐nitro‐2,3,4,5,8,9‐hexahydropyridone[1,2‐a]diazepine via one‐pot three component reaction of diamine, nitroketene dithioacetal (1,1‐bis(methylsulfanyl)‐2‐nitroethene), and coumarine‐3‐ carboxylic acid derivatives in EtOH under reflux conditions is reported. The advantages of this procedure are simplicity, easy purification, good yields, and catalyst‐free conditions. All products were confirmed by ¹H‐ and ¹³C‐NMR, IR, MS, and X‐ray crystal structure analyses.     

Resorcinarene supramolecular organocatalyst for functionalized 1-tetralone synthesis in aqueous medium

An efficient, straightforward and environmentally benign process has been developed for the synthesis of fluorenone and 1-tetralone derivatives using cyclic 1,3-dione, malononitrile and dialkylacetylenedicarboxylate as starting materials in aqueous medium. The reaction is favoured in presence of resorcin[4]arene which is effective as a reusable organocatalyst. The catalyst has been easily synthesized and characterized by ¹H, ¹³C NMR, IR, XRD and HRMS analyses. Resorcin[4]arene afforded the resulted products in a shorter time and in good yields. The recyclability of the catalyst was established up to 6th cycle by FT-IR and SEM images.