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The significant medicinal and pharmacological facts about chromenes (benzopyran) nucleus prompted us to focus on constructing unique chromenes with biological value. New chromene derivatives 2–15 were synthesized, and their antibacterial effectiveness was studied. The reaction of the 2-amino-4H-chromene derivative 1 with a variety of reagents such as acetic anhydride, formic acid, chloroacetyl chloride, cyclopentanone, ethyl acetoacetate, diethyl malonate, aldehydes, and isatin produced derivatives 2–13. Compound 1 was also treated with aromatic amines such as p-toluidine and/or benzene-1,4-diamine with formaldehyde, yielding derivatives 14 and 15, respectively; spectral techniques were used to confirm the predicted structures of all compounds. The antibacterial activity of the recently synthesized compounds was assessed against two types of bacteria, Bacillus subtilis and Escherichia coli. There is encouraging antibacterial activity in compounds 5 and 7. [ABSTRACT FROM AUTHOR]

By using easily accessible heterocyclic enamines, acetaldehyde (or formaldehyde) and primary amines as suitable precursors, a water-assisted three-component synthesis of new 3-oxothiazolo[3,2-c]pyridimines has been efficiently achieved in mild and semi-aqueous medium. All the cyclization reactions under optimized and catalyst-free conditions furnish the target compounds in 40–100% yields. Although cyclizations with arylamines in the presence of formaldehyde yield moderate to good yields, certain cyclizations involving aryl amines in the presence of acetaldehyde do not result in any product formation. Structural characterization of all the products were performed by means of FT-IR,1H and 13C NMR and HRMS analyses. Besides, some of the products demonstrated bacteriostatic effects in the antibacterial study conducted against S. aureus and S. epidermidis bacteria. [ABSTRACT FROM AUTHOR]

Synthesis of 2-aryl substituted benzoxazoles, benzothiazoles, and quinoxalinones via decarboxylative coupling of α-keto acids with 2-aminophenol, 2-aminothiophenol, and OPD (o-phenylenediamine), using K2CO3 as a base in water at room temperature, and as well as solvent-free grinding and the synthesis of benzoxazinones from the reaction of α-keto acids with 2-aminophenol at 60 °C have been reported. Both the protocols afforded a wide range of desired products with excellent functional group tolerance in yields of 87-99%. The major advantages of these approaches are catalyst-free protocol, short reaction times, straightforward workup, and chromatographyfree processing of the products. Additionally, to test the translational demand of this methodology, the synthesis of 2-(3,5-dichlorophenyl)- 6-methylbenzo[d]oxazole was carried out which is a key structure of tafamidis, a commercially available drug. [ABSTRACT FROM AUTHOR]

A one-pot protocol was developed to prepare new thiazol-2(3H)-imines in efficient yields. Therefore, the reaction of the appropriate aromatic amine, phenyl isothiocyanate and chloroacetone (ratio 1:1:1) was mediated using different solvents and bases. The optimized protocol was to conduct the reaction in ethanol at reflux in the presence of 1.2 equivalents of sodium acetate. The reaction produced the regioisomeric (Z)-N-aryl-3-phenylthiazol-2(3H)-imine, as detected by 1D and 2D NMR spectral data. Using a similar protocol, new arene- or chromene-linked thiazol-2(3H)-imines were prepared by the use of the respective α-bromoketones. The new products were screened against six different bacterial strains. In general, chromene-linked thiazol-2(3H)-imines displayed superior antibacterial activity over other products. Thiazol-2(3H)-imines linked to 6-methyl and 6-methoxy-2-oxo-2H-chromene units had the most effective antibacterial activity with MIC/MBC values of 2.0/4.0 and 1.9/3.9 µM, respectively, against Staphylococcus aureus, Streptococcus mutans, and Escherichia coli strains. [ABSTRACT FROM AUTHOR]

A highly efficient, one-pot, three-component Strecker reaction for the synthesis of α-aminonitriles from carbonyl compounds, amines, and potassium hexacyanoferrate (II) (K4[Fe(CN)6]) in the presence of a catalytic amount of humic acid catalyst in water at room temperature has been developed. Advantages of this methodology are use of inexpensive, commercially available, environmentally friendly and reusable organocatalyst, environmentally benign and inexpensive cyanide source, simple experimental and work-up procedure, high yields, room temperature reaction, water as a green solvent and scaled-up synthesis. Environmentally friendly, commercially available, inexpensive and reusable catalyst Environmentally friendly and inexpensive cyanide source High yields Simple operations and mild conditions Water as a green solvent Green synthesis [ABSTRACT FROM AUTHOR]

We report transamidation protocol to synthesize a range of secondary and tertiary amides from weakly nucleophilic aromatic and hetero-aryl amines with low reactive formamide derivatives, utilizing hydrochloric acid as catalyst. This current acid mediated strategy is beneficial because it eliminates the need for a metal catalyst, promoter or additives in the reaction, simplifies isolation and purification. Notably, this approach conventionally used to synthesize molecules on gram scales with excellent yields and a high tolerance for functional groups. [ABSTRACT FROM AUTHOR]

New series of diazenylschiff's bases of salicylaldehydes were synthesized. The new diazenylschiff's bases were synthesized by condensation reaction of 5-(3-bromophenyldiazo)salicylaldehyde with various amines such as aromatic amines, sulfa drugs, naphthalenes, aminoantipyrine and aminothaizoles. The antimicrobial activity for the synthesized diazenylschiff's bases was screened against various Gram-positive and Gram-negative bacteria as well as fungal strains. The mean values of the obtained inhibition zone diameter for the synthesized compounds suggested that most of the Schiff's bases possess significant antifungal activity against Aspergillus fumigatus. Most of the Schiff's bases possess moderate activity against Bacillus subtilis and Candida albicans. [ABSTRACT FROM AUTHOR]

Efficient procedures have been developed for the synthesis of novel series of bis(9,10-diaryl-hexahydroacridine-1,8-diones) in which the two acridine moieties were linked to aliphatic, aromatic, or heteroaromatic spacers via ether or ester linkages. The target products were obtained in good to excellent yields via a multi-component reaction of the appropriate aromatic amine, 5,5-dimethyl-1,3-cyclohexanedione, and the corresponding bis-aldehydes. The reactions were also proceeded to give the target products in good yields via a multi-component reaction of the appropriate cyclic enamines, and the corresponding bis-aldehydes under similar conditions. Bis-alkylation of the appropriate hexahydroacridine-1,8-dione with the corresponding dihalo compound in a basic medium was also proved to be an effective strategy for the synthesis of the target products. The multi-component reaction of the aromatic amine, bis-aldehydes, and barbituric acid or 1,3-dimethylbarbituric acid, instead of 5,5-dimethyl-1,3-cyclohexanedione, afforded the corresponding Knoevenagel condensation adducts in good yield and unfortunately, the expected bis-tetrahydropyrimido[4,5-b]quinolines could not be isolated. [ABSTRACT FROM AUTHOR]

Electrophilic amination reaction was performed with lower order and higher order organocuprates using acetone O-(4-Chlorophenylsulfonyl)oxime (1). It was proceeded smoothly at room temperature in the presence of organocuprates to provide the corresponding primary amines in good yields with 10 and 60 min, respectively. The primary amine yields of the electrophilic amination of bromomagnesium organocyanocuprates and dibromomagnesium diorganocyanocuprates were obtained 52–72% and 58–83%, respectively. We observed that higher order organocuprates were more successful than lower order organocuprates in the synthesis of functionalized arylamines by electrophilic amination. [ABSTRACT FROM AUTHOR]

A novel and highly efficient heterogeneous gold(I)-catalyzed hydroamination of allenamides with arylamines has been developed that proceeds effectively under mild conditions and offers a general and practical route for the synthesis of allylamino E-enamides with good to excellent yields and high stereoselectivity. The supported gold(I) catalyst can be reused at least seven times without any apparent decrease in the catalytic activity. [ABSTRACT FROM AUTHOR]

Nanocerium oxide mediated an efficient and green protocol has been described for the chemoselective N-tert-butyloxycarbonylation of amines under the solvent-free conditions at ambient temperature. Various aliphatic, aromatic and heteroaromatic amines were protected using developed protocol and several functional groups such as alcohol, phenol and ester were well tolerated under these conditions. The rapid reaction rate, mild conditions, very good functional group tolerance, excellent yield, solvent-free, easy recovery products and excellent catalyst recyclability are the advantages of this protocol. This makes the protocol feasible, economical and environmentally benign. [ABSTRACT FROM AUTHOR]

Ni(Salen) complexes as an efficient, homogeneous catalysts revealed a catalytic activity toward the one-pot synthesis of tetrahydropyridine derivatives through the pseudo five-component reactions of aromatic aldehydes, aromatic amines, and β-ketoesters in ethanol at room temperature. Mild reaction conditions, good yields, high diastereoseletivity, operational simplicity, and the absence of tedious separation procedures, clean reaction profiles, high atom economy, inexpensive starting materials, and environmentally benign catalyst are the key advantages of the present MCRs protocol. [ABSTRACT FROM AUTHOR]

In this study, we report a straightforward oxidative cross-coupling synthesis of carbodiimide tethered amino acid conjugates from amino acid-derived isocyanides and aryl amines mediated by I2/tert-butyl hydroperoxide. Using this protocol, the title compounds were obtained in good isolated yields. This protocol is of short reaction duration, base-free, racemization free and avoids the necessity of transition metal catalysts. [ABSTRACT FROM AUTHOR]

An efficient and facile approach for the synthesis of new quinoline derivatives was accomplished via reactions of 2-chloroquinoline-3-carbaldehyde with active methylene compounds, for example, 1,3-dimethylbarbituric acid, thiobarbituric acid and 2,4-dioxothiazolidine and aromatic amines through one-pot multi-component reaction (MCR) as sources of pyrimidine and thiazolidine derivatives bearing quinoline moiety. All compounds were synthesized via conventional and Microwave Irradiation conditions. The best results (short reaction times, pure products, high yield) were obtained by microwave irradiation. The synthesized derivatives were characterized by various physicochemical and spectral techniques from their analytical and spectral data. [ABSTRACT FROM AUTHOR]

Natural and synthetic naphthoquinones are known for a large number of biological activities. Lawsone (2-hydroxy-1, 4-naphthoquinone) is a simplest naturally occurring compound obtained from dried henna (Lawsonia inermis) leaves. In literature, some lawsone derivatives have been reported to exhibit anticancer activity. Hence, a clean and facile one-pot protocol was developed for the synthesis of new aminonaphthoquinones derived from lawsone by three-component Mannich reaction, at room temperature for potential anti-cancer application. Herein we present a small library of Mannich bases with different amines and aromatic aldehydes with moderate to high yield. Synthesized compounds were characterized using various spectroscopic techniques. The anticancer activity (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay) along with nuclear morphology assessment (4′,6-diamidino-2-phenylindole or DAPI staining), apoptosis assessment (acridine orange/ ethidium bromide staining), hemolysis and DNA ladder assay evaluated on human liver carcinoma cell line HepG2 are presented. [ABSTRACT FROM AUTHOR]

A straightforward and greener PEG-assisted protocol has been disclosed for the cascade synthesis of [1,3]Oxazino quinoline, and chromeno[1,3]oxazin derivatives via three component reaction of multifarious aromatic amines with formaldehyde and 4-hydroxyquinoline-2(1H)-one or 4-methylumbelliferone by using very convenient reaction conditions. This methodology represents a sustainable approach for rapid access to a library of diversity oriented highly pure [1,3]oxazino scaffolds with broad substrate scope. [ABSTRACT FROM AUTHOR]

In this paper, we report one-pot, three-component cyclo condensation of an aldehyde, an amine and thioglycolic acid to form 2,3-disubstituted-thiazolidin-4-one by using supported protic acid (Silica Chloride: SiO2-Cl) catalyst. The catalyst SiO2-Cl is compatible with a variety of aldehydes (aryl/heteroaryl) and the aromatic amines affording 2,3-disubstituted-thiazolidin-4-one analogs in 72–89% yields. Moreover, the supported catalyst was recycled several times without significant loss of catalytical activity [ABSTRACT FROM AUTHOR]

Allyl alkynoic esters were synthesized by the reaction of allyl amines and alkynoic acids via deaminative esterification. The reaction of allyl alkynoic esters with Pd(dba)2 and Xantphos in digylme at 110 °C for 12 h afforded the desired decarboxylated allyl alkynes in good yields. [ABSTRACT FROM AUTHOR]

The synthesis of various N-aryl 2-chloroacetamides has been described through chloroacetylation of the corresponding aryl amine. The chemical reactivity of N-aryl 2-chloroacetamides is attributed to the easy replacement of its chlorine atom by nucleophiles (namely; oxygen, nitrogen and/or sulfur). Furthermore, this nucleophilic substitution may accompanied by intramolecular cyclization to furnish miscellaneous heterocyclic systems as imidazole, pyrrole, thiazolidine-4-one and thiophene. [ABSTRACT FROM AUTHOR]

Hydrocarbons, benzylamines, and heteroaromatic-bearing amines have been efficiently employed as substrates in allylic and benzylic oxidations via C(sp3)–H bond activation by TBAI/TBHP in water. This operationally simple method allows access to ketones, nitriles, and amides in moderate to high yields and a regio- and chemoselective late-stage functionalization. [ABSTRACT FROM AUTHOR]

Herein, we report an efficient synthesis of N-nitrosamines from cyclic, aliphatic, benzylic, and aromatic secondary amines via a novel straightforward, efficient, and mild chemical process using sodium nitrite and Oxone in methanol as a solvent at 0–5 °C. The demonstrated methodology accounts well for the parameters like cost-effective, short reaction time, clean and safe handling along with good to excellent yields. [ABSTRACT FROM AUTHOR]

A rapid and efficient diesterification reaction of aromatic carboxylate with 1,4-dibromobutane was carried out in water at 100 °C in the presence of base and phase transfer catalyst under focused microwave irradiation. This microwave-promoted protocol offers an atom-efficient and environment-friendly approach to synthesize butamethylenediesters in high yield. [ABSTRACT FROM AUTHOR]

In this article, we report the approach to the substituted ureas based on the reaction of 1-(3,3-diethoxypropyl)ureas with phenols. Depending on the nature of the phenol and urea the reaction leads either to diarylpropane and dibenzoxanthene derivatives or calixarenes. The proposed method benefits from mild reaction conditions, high product yields and operational simplicity. [ABSTRACT FROM AUTHOR]

A novel, efficient and convenient procedure has been developed for the synthesis of 2-(4-amino-substituted benzylidene)indanone derivatives. In the first step, the reaction of 4-fluorobenzaldehyde with 5, 6-dimethoxy-2, 3-dihydro-1H-inden-1-one in the presence of NaOH in EtOH was described. In the next step, a variety of aliphatic and aromatic amines were reacted with 2-(4-fluorobenzylidene)-5, 6-dimethoxy-2, 3-dihydro-1H-Inden-1-one via aromatic substitution (SNAr) reaction to produce 2-(4-aminobenzylidene)-5, 6-dimethoxy-2, 3-dihydro-1H-Inden-1-one derivatives as a novel class of 1-indanones. These products have been successfully prepared in good to excellent yields. 1 H and 13 C NMR, FT-IR spectroscopy and CHN analysis supported the proposed structures of the products. [ABSTRACT FROM AUTHOR]

Reaction of aromatic amines with tertiary enamides was performed inn-hexane in the presence of acetic acid as an inexpensive and green catalyst at room temperature. This protocol provides the protected aminals through Markovnikov addition reaction with high to excellent yields and regiospecificity. In addition, this procedure was expanded for the synthesis of aminals from commercially available sulfa drugs such as sulfathiazole and sulfabenzamide. [ABSTRACT FROM PUBLISHER]

An efficient, catalyst-free, microwave-assisted approach has been developed for the synthesis of 4-azo-butyenolides derivatives by condensing tetronic acid with various anilines. This approach exhibited good functional group compatibility and produced the desired products in good to excellent yields in just 30–40 min. This approach can be seen as a better alternative to protocols with long reaction times used for the synthesis of these compounds, which are synthons for the obtaining of quinolines. [ABSTRACT FROM PUBLISHER]

The intramolecular Pauson–Khand cyclization in the presence of both aniline and nitrobenzene was used to improve the construction ofN-nitrobenzenesulfonyl-protected 3-azabicyclo[4.3.0]nonane skeletons. We found that aniline enhanced the cyclization and that nitrobenzene prevents the concurrent reduction in this process. This combination of mediators allows for the efficient synthesis of bioactive azabicyclic nonane-type alkaloids and the use of milder deprotection conditions in the synthetic route. [ABSTRACT FROM AUTHOR]

An efficient transition metal-free allylic nucleophilic α -substitution of Morita–Baylis–Hillman alcohols with both aliphatic and aromatic amines in refluxing toluene, using activated molecular sieves as additives, is described herein. The reaction proceeded with exclusive α -regioselectivity in moderate to excellent yields with the formation of water as the sole by-product. Under the same conditions, upon treatment of some thiols with the title substrates, allylic sulfides were obtained in excellent yields and high regioselectivity. [ABSTRACT FROM AUTHOR]

A simple protocol for the preparation of functionalized allylic amines under mild, transition-metal-free conditions from the reaction of Morita–Baylis–Hillman (MBH) bromides with amines is described herein. The treatment of the MBH bromides with various amines in the presence of NaI and Et3N in aqueous acetone solution and at room temperature affords the corresponding functionalized allyl amines in moderate to good yields (45–87%). The reaction is rapid and carried out at room temperature. [ABSTRACT FROM PUBLISHER]

An efficient pathway for the synthesis of the aminobenzophenone derivatives via Friedel–Crafts benzoylation using copper triflate as catalyst is proposed. New derivatives are synthesized. The copper triflate could be easily recovered and reused without loss of catalytic activity. Both the use of ionic liquids and microwave heating turned out to be fruitful. [ABSTRACT FROM PUBLISHER]

Stirring an equimolar mixture of ninhydrin1and 2-aminochromen-4-ones2in CH3COOH at room temperature produced 6a,11a-dihydroxy-6H-chromeno[2,3-b]indeno[2,1-d]pyrrole-11,12(6aH,11aH)-diones3, which on heating with aromatic amines6in acetic acid produced 11b-hydroxy-7-N-arylimino-6H-chromeno[2,3-b]isoindolo[1,2-e]pyrrole-12,13(11bH)-diones7. [ABSTRACT FROM PUBLISHER]

One-pot, three-component synthesis of spiro[diindenopyridine-indoline]triones has been reported via the reaction of 1,3-indandione, aromatic amines, and isatins with (PEG-OSO3H) as an efficient, polymeric acid surfactant–based catalyst in water and also in presence of acidic ionic liquid [NMP]H2PO4, which acts both as a medium and catalyst under conventional heating and ultrasonic irradiation. The reactions were complete in short reaction times with excellent yield of products. Surfactant-based PEG-OSO3H could be recycled and reused several times without any significant loss of activity. The compounds exhibit fluorescence in methanol with large Stokes shift. [ABSTRACT FROM AUTHOR]

A simple, scalable, ligand-free, and metal-free protocol for arylation of amines and monoarylation of symmetrical diamines with diheteroaryl halides in the presence of brine solution has been developed. The protocol has broad structural applicability for chemoselective monoarylation of a wide variety of symmetrical, cyclic, and acyclic aliphatic diamines. The protocol is also applicable for selective arylation of aliphatic amine in the presence of aromatic amine. [ABSTRACT FROM PUBLISHER]

Ammonium chloride, which is a very inexpensive and readily available reagent, can efficiently catalyze three-component, one-pot condensation reactions of 2-amino-benzoic acid esters, ortho esters, and aromatic amines to afford the corresponding 4(3H)-quinazolinones in good to excellent yields under solvent-free conditions. [ABSTRACT FROM AUTHOR]

A new, one-pot, three-component reaction for the synthesis of benzo[c][2,7]naphthyridines has been achieved from aromatic amines, aromatic aldehydes, and N-carbethoxy-4-piperidone in the presence of a catalytic amount of ceric ammonium nitrate in good yields at room temperature. The advantages of this procedure are mild reaction conditions, low toxicity, and the use of inexpensive reagents. Apart from milder and environmentally benign conditions, this method involves a simple, reliable approach to give good yields of the desired products and is compatible with a wide range of functional groups. [ABSTRACT FROM AUTHOR]

This work reports an efficient protocol for the coupling reaction of aryl iodides/boronic acids with sodium azide to aryl azides/amines in the presence of copper bis(2,2,6,6-tetramethyl-3,5-heptanedionate) Cu(TMHD)2catalyst. The Cu(TMHD)2catalyst is a structurally well-defined,O-containing, air- and moisture-stable, transition-metal complex and works at mild reaction conditions. It was observed that aryl azides can be reduced further to corresponding aniline derivatives using the same catalyst under basic reaction conditions for a prolonged period. [Supplementary materials are available for this article. Go to the publisher's online edition ofSynthetic Communications®for the following free supplemental resource(s): Full experimental and spectral details.] [ABSTRACT FROM PUBLISHER]

Hexamethylene bis(N-methylimidazolium) bis(dichloroiodate) (HMBMIBDCI), an ionic liquid iodinating reagent, have been prepared and characterized. Its ability to perform iodination reactions with a variety of substrates has been explored. In general, iodination reactions of aromatic and heteroaromatic amines proceed with good yields in the absence of solvent. Reactions of terminal alkynes in the presence of 1,8-diazabicyclo [5.4.O] undec-7-ene and tetrahydrofuran have been investigated as well. [Supplementary materials are available for this article. Go to the publisher's online edition ofSynthetic Communications®for the following free supplemental resource: Full experimental and spectral details.] [ABSTRACT FROM PUBLISHER]

A general methodology “malonic ester amide synthesis” has been demonstrated, which usesα-substituted/unsubstituted diethyl malonates for the decarboxylative acylation of various aromatic/heteroaromatic primary/secondary amines to form one-carbon homologated amides, thus providing easy access to amides with odd/even chain lengths and an array of substituents on the alkyl/aryl part while avoiding use of acyl chlorides or peptide coupling reagents. Supplemental materials are available for this article. Go to the publisher's online edition ofSynthetic Communications®to view the free supplemental file. [ABSTRACT FROM AUTHOR]

Novel bromo-substituted derivatives of dibenzo-tetraaza and dibenzo-dioxadiaza[14]annulenes B–G were synthesized by a twofold condensation reaction of a symmetrical bromo-substituted vinamidinum salt A with ortho-diamino- and ortho-amino-hydroxyarenes such as 1,2-diaminobenzene, 1,2-diamino-4,5-dimethylbenzene, 2,3-diaminonaphthalene, 1,2-diamino-4-methylbenzene, 2-amino-1-hydroxybnzene, and 2-amino-1-hydroxy-5-methyl-benzene in acetonitrile/acetic acid as reaction medium. The ultraviolet/visible spectral behavior of these [14]annulenes was examined in dimethyl sulfoxide (DMSO). Elemental analysis, infrared,1H NMR,13C NMR, and mass spectra confirm the molecular structure of the newly synthesized compounds. [ABSTRACT FROM AUTHOR]

A novel series of potential biologically active new cinnamoyl amides were synthesized in good yield and short reaction times. We have studied the one-pot, solvent-free reaction of cinnamic acid derivatives with aromatic amines using 1,3-dicyclohexylcarbodiimide under microwave irradiation in the presence of small quantities of dimethylformamide to improve energy transfer. [ABSTRACT FROM AUTHOR]

An efficient method has been developed for the Pd-catalyzed cross-coupling reactions of electron-deficient heteroaromatic amines with heteroaryl halides. The optimized reactions used Pd2(dba)3 as catalyst, 1,1′-bis(diphenylphosphino)ferrocene (DPPF) as ligand, and Cs2CO3 as base. The Pd-catalyzed cross-coupling reactions of several rarely reported electron-deficient heteroaromatic amines were successfully accomplished in good yields. [ABSTRACT FROM AUTHOR]

Thiomorpholine 1,1-dioxides were prepared with double Michael addition reaction of aromatic amines to divinyl sulfone catalyzed by boric acid / glycerol in water. This catalyst system was also used for the Michael addition reaction of aromatic amines to electron-deficient alkenes. The reaction is simple and green and gives good to excellent yields. [ABSTRACT FROM AUTHOR]

Synthesis of a series of 1aR,2S,4aS-hexahydropyrrolo[3,4-b]quinolines has been achieved by the intramolecular cyclization reaction of aldimines derived from aromatic amines and (S)-2-(N-(3-methylbut-2-enyl)-N-tosyamino)-3-methylpropanal/(S)-2-(N-(3-methylbut-2-enyl)-N-tosyamino)-3-phenylpropanal in acetonitrile with InCl3 as a catalyst, in excellent yields and in short duration of time, under mild conditions. [ABSTRACT FROM AUTHOR]

A practical method has been developed for reduction of C-N double bond in oximes, imines, and hydrazones with sodium borohydride catalyzed by Raney Ni. The reactions were carried out in basic aqueous solution, and the desired products were obtained in moderate yields after a simple procedure. This method can be applied to synthesize simpler aliphatic or aromatic amines and its analogs. [ABSTRACT FROM AUTHOR]

N-Substituted pyrroles were synthesized under neat conditions by the reaction of aromatic amines with 2, 5-dimethoxytetrahydrofuran in excellent yields. [ABSTRACT FROM AUTHOR]

A highly efficient method for the synthesis of 1,4-phenylenedithioureas promoted by microwave irridiation is reported. It is based on the nucleophilic addition reaction of 1,4-phenylenediisothiocyanate to aromatic amines under solvent- and catalyst-free conditions. The reaction has the advantages of short reaction time, good yields, and environmental acceptability. [ABSTRACT FROM AUTHOR]

A simple, efficient, and recyclable catalytic system of CuI-poly(ethylene glycol) (PEG) was developed for the N-arylation of imidazoles with aryl halides to afford corresponding N-arylimidazoles in good to excellent yields under mild conditions and free of any additional ligands and solvents. The isolation of the products was readily performed by simple extraction with ether, and the catalytic system could be reused without remarkable loss of activity even after six runs.[image omitted] [ABSTRACT FROM AUTHOR]

Natural α-amino acids were proven to be ecofriendly and recyclable catalysts for the carboxylation of aziridines with CO2 without utilization of any organic solvents or additives. Notably, a series of 5-aryl-2-oxazolidinones were obtained in good yield together with excellent chemo- and regioselectivity under mild conditions using proline as the catalyst. Notably, the catalyst could be recycled more than five times after a simple separation procedure without appreciable loss of catalytic activity. This process represents a promising strategy for homogeneous catalyst recycling.[image omitted] [ABSTRACT FROM AUTHOR]

A new approach for the synthesis of monosubstituted arylferrocenes based on the coupling of aryldiazonium salts with ferrocene using PEG-1000 as an efficient phase-transfer catalyst was developed. The present method is applicable to many kinds of substituted aromatic amines, providing good to excellent yields of desired products. [image omitted] [ABSTRACT FROM AUTHOR]

2-Phenyl-5,6,7,8-tetrahydro-4H-benzothieno[2,3-d][1,3]oxazin-4-one (4) was reacted with either aliphatic or aromatic primary amines such as benzylamine, cyclohexylamine, p-toluidine, and/or p-anisidine to give carboxamide derivatives 5a-d, respectively. A bifunctional nucleophile such as ethanolamine was also reacted with 4, giving the carboxamide derivative 5e. Aminolysis of 4 with secondary amines such as piperidine and/or morpholine afforded the benzamide derivatives 6a and/or 6b, respectively. Fusion of 4 with hydrazine hydrate yielded the pyrimidine derivative 7 and carbohydrazide derivative 8. Thiation of 4 with phosphorous pentasulfide gave thienothiazine derivative 9, which reacted with benzylamine to give the pyrimidine derivative 10. Carbon nucleophiles such as ethyl cyanoacetate and/or malononitrile were subjected to react with 4 to give oxopropanoate 11 and/or oxopropanoic acid 12 derivatives, respectively. Microwave irradiation of 4 and formamide yielded the pyrimidinone derivative 13, which were subjected to react with phosphorous pentasulfide, a mixture of phosphorous oxychloride and phosphorous pentachloride and/or methyl iodide, to give 14, 15, and/or 16, respectively. [image omitted] [ABSTRACT FROM AUTHOR]