Three-Component Coupling Synthesis of Diversely Substituted N-Aryl Pyrroles Catalyzed by Iron(III) Chloride

An efficient and operationally simple three-component coupling synthesis of varieties of N-aryl substituted pyrroles is described in the presence of sustainable and environmentally benign metal catalyst, FeCl₃. This method provides a straightforward approach for the synthesis of N-aryl substituted pyrroles in good yields from easily accessible starting materials such as nitroalkenes, 1,3-dicarbonyl compounds, and primary aromatic amines. The reaction proceeds through a catalytic sequence of Fe(III)-catalyzed amination/Michael/cycloisomerization reactions.

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A modified approach to 2-(N-aryl)-1,3-oxazoles: application to the synthesis of the IMPDH inhibitor BMS-337197 and analogues

[structure: see text] A modified approach to the synthesis of 2-(N-aryl)-1,3-oxazoles, employing an optimized iminophosphorane/heterocumulene-mediated methodology, and its application to the synthesis of BMS-337197, a potent inhibitor of IMPDH, are described.     

Alkyl- und Arylsulfensäureanilide durch Cycloeliminierung von Alkenen aus Sulfimiden, 2. Thermolyse von 3-Alkylthiopropannitril-bzw. 3-Alkylthiopropansäuremethylester-S-(N-aryl)-imiden

Summary A series of alkyl- and arylsulfenanilides has been prepared by thermal cycloelimination of acrylonitrile or methyl acrylate from N-aryl sulfimides derived from 3-alkylthio-propionitriles or methyl 3-alkylthio-propanoates. Compared to reactions in earlier studies [1] cycloelimination proceeds much faster at very mild conditions, thus allowing a one-pot synthesis of sulfenanilides from corresponding 3-alkyl-thio-propionitriles or 3-alkylthio-propanoates.

     

A mild and simple synthesis of N-aryl substituted toluenesulfamides under solvent-free conditions

N- aryl substituted benzenesulfamides are often used as heating-sensitive recording material1, thermal printing material2, sensitizer3 and developer4. Moreover, some of the benzenesulfamides have antifungal activities5. Many methods have been described for preparation of sulfamides. They are used to carry out in solvent8 or in solid phase condition9. These methods required solvent or solid support and even required heating or cooling. At the same time, the process of these methods is complex. Now we have developed a new method to prepare N-aryl substituted toluenesulfamides under solvent-free conditions.In recent years, solvent-free technology has gained popularity in organic synthesis. For instance,solidstate reaction and microwave reaction have received considerable attention. Solvent-free synthesis of amides has been reported10-11. This technology has many advantages such as high efficiency and selectivity, easy separation and environmental acceptability. All these merits are in accord with green chemistry's requirements of energy-saving, high efficiency and environmental benefits.In our paper, we used a simple and efficient method for preparing N-aryl substituted toluenesulfamides under solvent-free conditions, as a replacement for classic solvent, which gives many environmental benefits.All reactions were completed at room temperature by co-grinding in an agate mortar for 3-20min and the results are shown in Table 1.In conclusion, we have developed an efficient and convenient method of preparation N-aryl substituted toluenesulfamides in high yields. It symbols an improvement for synthesis of benzenesulfamides.     

Nickel-catalyzed C-N crossing coupling reaction: The synthetic method for N-aryl substituted indenoindole

A nickel-based catalyst was employed for the first time in the crossing-coupling of indenoindoles with bromo-/iodoarenes. A simple and practical method was provided for the synthesis of N-aryl substituted indenoindole and the mechanism of this reaction was discussed.     

A new efficient synthesis of pyranoquinolines from 1-acetyl N-aryl cyclopentanecarboxamides

A new efficient synthesis of pyrano[2,3-b]quinoline derivatives is developed via the H2SO4-mediated tandem cyclization/ring-opening/recyclization reaction of readily available 1-acetyl N-aryl cyclopentanecarboxamides, during which a novel ring-cleavage fashion of the cyclopentane unit is involved and possible mechanisms are discussed.     

Synthesis of indoles via domino reaction of N-aryl amides and ethyl diazoacetate

A general and concise synthesis of functionalized indoles via domino reaction of N-aryl amides and ethyl diazoacetate has been developed. The methodology offers a great potential for the synthesis of biologically active and naturally occurring indole derivatives.     

Three-component synthesis of 6-aryl-4-methyl-2-oxo-1,2,3,6-tetrahydropyrimidine-5-(N-aryl)carboxamides

A three-component synthesis using acetoacetanilides and a mixture of an aromatic aldehyde and urea yields 6-aryl-4-methyl-2-oxo-1,2,3,6-tetrahydropyrimidine-5-(N-aryl)carboxamides.     

Synthesis of cytimidine through a one-pot copper-mediated amidation cascade

A concise synthesis of cytimidine was developed utilizing tandem Cu-mediated N-aryl amidations followed by global deprotection. This sequence exploits a regioselective coupling of an iodobenzamide with a halopyrimidine that allows the union of three fragments in a single synthetic manipulation and will permit the efficient and rapid diversification of the cytimidine core.     

新型芳磺酰基色氨酸酯以及芳磺酰基谷氨酸二酯类化合物的合成与生物活性研究

在乙酰羟酸合成酶(AHAS)与磺酰脲类化合物复合物晶体结构的基础上, 利用分子对接法进行MDL/ACD三维数据库虚拟筛选, 得到了部分结合能较低的小分子化合物结构. 对其中的芳磺酰基色氨酸酯以及芳磺酰基谷氨酸二酯类化合物进行了合成, 共合成22个具有潜在活性的新衍生化合物, 其结构通过核磁、质谱、红外及元素分析验证, 并对所有新化合物进行了体内、体外活性测试. 初步的体外生物活性测试结果表明, 两类化合物对AHAS具有较低的抑制性; 体内生物活性测试结果表明, 化合物4d, 4g和4k具有一定的除草活性, 在100 μg/mL的浓度下, 它们对油菜根长的抑制率分别为70.8%, 52.4%和50.2%.     

A one-pot synthesis of tertiary amines from amines,lactams and urethanes

A one-pot synthesis of unsymmetrical tertiary amines from amides, lactams and urethanes has been developed. The reaction is general for all cases examined with the exception of N-aryl containing examples, which are not accessible by this method.     

Novel N-aryl and N-heteroaryl sulfamide synthesis via palladium cross coupling

A novel and efficient synthesis of N-aryl and N-heteroaryl sulfamides via an intermolecular palladium-catalyzed coupling process has been developed. The reactions proceeded with good to excellent yields and were tolerant of a wide range of functional groups. [reaction: see text]     

Efficient and versatile synthesis of indoles from enamines and imines by cross-dehydrogenative coupling

Complement for Fischer: An efficient palladium-catalyzed indole synthesis proceeds by the intramolecular cross-dehydrogenative coupling of N-aryl imines under mild conditions using molecular oxygen as the sole oxidant. This practical method relies on anilines and ketones as starting materials (and thus the same retrosynthetic disconnection as the Fischer indole synthesis) and will likely become a popular route.     

Practical synthesis of new and highly efficient ligands for the Suzuki reaction of aryl chlorides

A practical synthesis of a novel class of phosphine ligands, phosphino substituted N-aryl pyrroles (PAP ligands), has been developed. These ligands are applied in the palladium-catalyzed coupling of a variety of aryl and heteroaryl chlorides with phenylboronic acid showing exceedingly high turnover numbers at mild reaction temperatures and even at room temperature.     

Stereospecific desulfinylation of sulfinylaziridines with ethylmagnesium bromide: A novel synthesis of (Z)-N-arylaziridines

A novel synthesis of (Z)-N-arylaziridines was realized by the stereospecific desulfinylation of (E)-(N-aryl)sulfinylaziridines which were synthesized from 1-chloroalkyl p-tolyl sulfoxides and N-arylimines in high yields.     

Aromatic nucleophilic substitution or CuI-catalyzed coupling route to martinellic acid

Condensation of beta-amino ester 8b with triflate 7 gives N-aryl amino ester 11, which is converted into 2-substituted 4-oxoquinoline 4 using an intramolecular Dieckmann reaction as the key step. CuI-mediated coupling of beta-amino ester 8a with 1,4-diiodobenzene followed by an intramolecular acylation and Pd-catalyzed carbonylation provide another manner to 4. Alkylation of 4 and subsequent reductive amination deliver the cyclic imine 14, which is transformed into triamine 3 by ordinary operations. Guanylation of 3 under mild condition followed by deprotection results in the synthesis of martinellic acid 1.     

One-pot synthesis of N-aryl propargylamine from aromatic boronic acid,aqueous ammonia,and propargyl bromide under microwave-assisted conditions

A facile,one-pot synthesis of N-aryl propargylamine from aromatic boronic acid,aqueous ammonia,and propargyl bromide has been achieved under microwave-assisted conditions.The reactions can be smoothly completed within a total 10 min through a two-step procedure,including copper-catalyzed coupling of aromatic boronic acids with aqueous ammonia and following propargylation by propargyl bromide.     

Synthesis of Functional Olefins Using the Wittig-Horner Reaction in Different Media

A convenient procedure for the synthesis of E-oletins bearing electron donor-acceptor groups is reported. A new diethyl N-aryl aminobenzylphosphonate (1d) was synthesized. Reactivity of Wittig-Homer reaction is compared. Expansion of the π-conjugate chain involves the reduction of N-methoxy-N-methyl amide to aldehyde by reaction with DIBAL-H.     

Facile and Simple Synthesis of N-Alkyl and N-Aryl 2-Benzazepines by Nucleophilic Heteroannulation

An efficient and practical synthesis of N-alkyl and N-aryl 2-benzazepine has been developed. The key steps involved in the synthesis were palladium-mediated Heck reaction followed by aza heterocyclic ring construction by nucleophilic heteroannulation. This four-step sequence synthetic protocol gave moderate to good yields for a wide range of substrates. Subsequently, functionalization of the synthesized compound was carried out under Heck and Suzuki reaction conditions.     

New and Effective Route to N-Alkyl and N-Aryl 2-F-Alkylethylamines

A new and effective procedure is described for the synthesis of N-alkyl and N-aryl 2-F-alkylethylamines avoiding the formation of 2-F-alkylethylethenes usually occuring in the N-alkylation of 2-F-alkylethyl iodides by amines.