以淀粉溶液为催化剂一锅三组分法合成四氢苯并[b]吡喃和3,4-二氢吡喃并[c]苯并吡喃衍生物(英文)

Tetrahydrobenzo[b]pyran and 3,4-dihydropyrano[c]chromene derivatives were synthesized via a one-pot three-component condensation of aromatic aldehydes with malononitrile and dimedone or 4-hydroxycoumarin in excellent yields in the presence of starch solution as a highly efficient homogenous catalyst.The use of a nontoxic and biodegradable catalyst,simple work-up procedure,and short reaction time are advantages of this method.     

A Mild and Environmentally Benign Synthesis of Tetrahydrobenzo[b]pyrans and Pyrano[c]chromenes Using Pectin as a Green and Biodegradable Catalyst

Pectin was applied as a green and biodegradable catalyst for the one‐pot three‐component synthesis of tetrahydrobenzo[b]pyrans and pyrano[c]chromenes, from the condensation between aromatic aldehydes, malononitrile, and dimedone or 4‐hydroxycumarine at ambient temperature. This protocol has many advantages such as mild conditions, high yields, environmental benignity, simple work‐up procedures, short reaction time, as well as the use of a natural, easily accessible, convenient handling, and inexpensive catalyst. Another advantage of this method is that the products do not require further purification such as column chromatography.     

One‐pot Synthesis of Tetrahydrobenzo[b]pyrans Catalyzed by PEG‐1000 Bridged Primary Amine Functionalized Dicationic Ionic Liquid in Water

A novel poly (ethylene glycol) bridged primary amine functionalized dicationic ionic liquid ([PA‐PEG₁₀₀₀‐DIL][BF₄]) was synthesized and characterized by ¹H‐NMR, ¹³C‐NMR, FT‐IR and ESI‐MS. The thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis indicated the high thermal stability of [PA‐PEG₁₀₀₀‐DIL][BF₄]. It was used as an efficient and recyclable catalyst for the synthesis of substituted tetrahydrobenzo[b]pyrans through a one‐pot three‐component condensation of aromatic aldehydes, malononitrile and dimedone in 86% ～ 96% yields within 10 ～ 30 min in water. This method offers several advantages such as mild reaction conditions, simple operation and environmental friendliness. Furthermore, the catalyst could be easily recovered and reused for at least five runs without obvious loss of catalytic activity.     

Effective one-pot synthesis of tetrahydrobenzo[b]pyran derivatives using nickel Schiff-base complex immobilized on iron oxide nanoparticles

Nickel Schiff-base complex immobilized on silica-coated Fe₃O₄ as a heterogeneous catalyst was designed and characterized by different techniques, such as Fourier transform infrared (FT-IR), X-ray powder diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), inductively coupled plasma (ICP) and vibrating sample magnetometry (VSM) thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET). The synthesized nanocatalyst has been explored as a new and efficient recyclable heterogeneous catalyst for the one-pot three-component synthesis of tetrahydrobenzo[b]pyran derivatives. The reaction proceeds smoothly to supply the respective products in excellent yields and low reaction times. The catalyst can be easily recovered by a magnetic field and reused for eight consecutive reaction cycles without significant loss of activity.     

Novel Efficient Method for Synthesis of N_(1,4)-Disubstituted-1,4-benzodiazepine-2,5-diones

A novel and efficient method was developed for the liquid-phase synthesis of N1,4-disubstituted-benzodiazepine-2,5-diones with 2-chloro-5-nitrobenzoic acid as initiating material via 4 step reactions containing esterification,Ulmn reaction,acylation,alkylation and cyclization. The reaction conditions were mild and the overall yields of the products ranged from 45% to 71%.     

Synthesis of 1-alkyl-3-arylamino-pyrrole-2,5-diones

Reaction of 1-alkyl-3-alkylaminopyrrole-2,5-diones with primary arylamine hydrochlorides in methanol or DMSO gives 1-alkyl-3-arylaminopyrrole-2,5-diones which could also be obtained from the reaction of arylaminofumarates with primary aliphatic amines. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1001–1007, July, 2007.     

水相中无催化剂合成四氢苯并吡喃衍生物

水相中无催化剂合成了2-氨基-7,7-二甲基-5-氧代-4-芳基-4H-苯并吡喃-3-氰基-5,6,7,8-四氢苯并[b]吡喃,其结构经1H NMR,IR和元素分析表征。     

Knoevenagel‐Michael‐cyclocondensation Tandem Reaction of Malononitrile,Various Aldehydes and Dimedone Catalyzed by Sulfonic Acid Functionalized Pyridinium Chloride as a New Ionic Liquid and Catalyst

New ionic liquid sulfonic acid functionalized pyridinium chloride [Pyridine–SO₃H]Cl was used for the synthesis of tetrahydrobenzo[b]pyran derivatives by the one‐pot three component condensation reaction of various aldehydes, dimedone and malononitrile at 95 ºC under solvent‐free conditions.     

几类4－取代苄基－2，6－哌嗪二酮的合成

介绍了４类具有络合性质或潜在的络合性质的４－取代苄基－２，６－哌嗪二酮化合物的合法。所合成的化合物中有些表现出明显的体外抑制白血细胞Ｐ３８８生长的活性。     

Synthesis of 2-aryl-5-alkyl-7-methoxylbenzo[b]furan derivatives

A series of 2-aryl-5-alkyl-7-methoxylbenzo[b]furan derivatives have been synthesized by utilizing the coupling of methyl 3-methoxy-4-hydroxy-5-bromocinnamate with cuprous phenylacetylide as the key step.The structures of the new compounds were confirmed by1H NMR,IR and MS.The structure of compound 14 was further confirmed by single crystal X-ray.Compound 17 showed cytotoxic activity against human lung carcinoma A549.     

Synthesis of Bridged Tetrahydrobenzo[b]azepines and Derivatives through an Aza-Piancatelli Cyclization/Michael Addition Sequence

Herein, we report the preparation of bridged tetrahydrobenzo[b]azepines, which was accomplished through an aza-Piancatelli cyclization/Michael addition sequence in a one-pot fashion from readily available precursors. It is noteworthy that a general method to access these scaffolds was hitherto unprecedented. Additionally, the multifaceted aspects of this process have been exemplified through its application to the synthesis of 2-azabicyclo[3.2.1]octanes and bridged tetrahydrobenzo[b]oxepines, along with post-derivatizations.     

Molecular Iodine: An Efficient Catalyst for the Synthesis of Tetrahydrobenzo[b]pyrans

An iodine/DMSO system is introduced as an excellent catalyst in three‐component coupling reactions of tetrahydrobenzo[b]pyran synthesis. The reaction proceeds quickly under very mild reaction conditions.     

KF-蒙脱土催化下2-氨基-3-氰基-4-芳基-7,7-二甲基-5-氧代-4H-5,6,7,8-四氢苯并[b]吡喃的合成

以KF-蒙脱土为催化剂, 取代肉桂腈与5,5-二甲基-1,3-环己二酮在95%乙醇中回流反应得2-氨基-3-氰基-4-芳基-7,7-二甲基-5-氧代-4H-5,6,7,8-四氢苯并[b]吡喃, 此方法快速、方便、高效, 同时考察了溶剂、催化剂对反应的影响.     

Synthesis of 2-Acetoxy- and 2-Hydroxy-2,3-dihydronaphtho[1,8-bc]pyran

Summary 2-Acetoxy- and 2-Hydroxy-2,3-dihydronaphtho[1,8-bc]pyranes were synthesized by decomposition of 1-hydroperoxy-1,2-dihydroacenaphthylene in acetic acid in the presence of perchloric acid.

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Synthese von 2-Acetoxy- und 2-Hydroxy-2,3-dihydronaphtho[1,8-bc]pyran

Zusammenfassung 2-Acetoxy- und 2-Hydroxy-2,3-dihydronaphtho[1,8-bc]pyrane konnten durch Zersetzung von 1-Hydroperoxy-1,2-dihydroacenaphthylen in Essigsäure in Anwesenheit von Perchlorsäure synthetisiert werden.

     

水中"一锅法"合成2-氨基-3-氰基-4-芳基-7,7-二甲基-5-氧代-4H-5,6,7,8-四氢苯并[b]吡喃

报道了以十二烷基苯磺酸(DBSA)为催化剂,芳醛、丙二腈和5,5-二甲基-1,3-环己二酮为原料于水中一步生成2-氨基-3-氰基-4-芳基-7,7-二甲基-5-氧代-4H-5,6,7,8-四氢苯并[b]吡喃.该方法具有产率高、操作简便、对环境友好、催化剂可重复使用等优点.     

Synthesis of 3-Hetaryl-1,2,4,5-tetrahydropyrrolo[1,2-a]quinazoline-2,5-diones

A convenient method has been developed for the synthesis of 3-hetaryl-1,2,4,5-tetrahydropyrrolo[1,2-a]quinazoline-2,5-diones by the interaction of 4-chloro-2-hetaryl-3-oxobutyronitriles with substituted anthranilic acids.     

水中2-氨基-3-氰基-4-芳基-7，7-二甲基-5-氧代4H-5，6，7，8-四氢苯并[b]吡喃的洁净合成

在水溶剂中在三乙基苄基氯化铵（TEBA）存在下，取代肉桂腈与5，5-二甲基- 1，3-环已酮反应为2-氨基-3-氰基-4-芳基-7，7-二甲基-5-氧代-4H，5，6，7，8- 四氢苯并[b]吡喃提供了一种快速、方便、高效和洁净的合成方法。     

Ytterbium triflate hydrate catalyzed Michael addition and cyclocondensation of α,β-unsaturated ketones with active methylene compounds

Catalyzed by ytterbium(Ⅲ) triflate hydrate [Yb(OTf)3.xH2O], the Michael addition and cycloeondensation of α,β-unsaturated ketones with active methylene compounds to afford the 1,4-adducts and benzo[b]pyran derivatives, respectively were studied.