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A novel Brønsted acidic ionic liquid namelyN,N-diethyl-N-sulfoethanamminium hydrogen sulfate ([Et3N-SO3H]HSO4) was synthesized, and characterized using FT-IR,1H NMR,13C NMR, and mass data. Then, its catalytic activity was examined for the preparation of triazolo[1,2-a]-indazole-triones and 2H-indazolo[2,1-b]phthalazine-triones by the one-pot multi-component condensation of arylaldehydes with dimedone and 4-phenylurazole/2,3-dihydrophthalazine-1,4-dione under solvent-free conditions. [Et3N-SO3H]HSO4efficiently promoted the reaction to afford the products in high yields and in short reaction times. [ABSTRACT FROM AUTHOR]

Di-sulfonic acid imidazolium chloroaluminate ([Dsim]AlCl4) as a new acidic and heterogeneous catalyst was applied to the preparation of N-sulfonyl imines via the condensation of sulfonamides with aldehydes as well as isatin under solvent-free conditions. Turn-over frequency (TOF) value of the catalyst was many times better than the previous reported catalysts. [Supplementary materials are available for this article. Go to the publisher's online edition ofPhosphorus, Sulfer, and Silicon and the Related Elementsfor the following free supplemental files: Additional text and figures.] [ABSTRACT FROM PUBLISHER]

The article presents a study which investigates the ionic liquid [Et3NSO 3H]Cl as new Brønsted acidic catalyst for the synthesis of N-Sulfonylimines, imidazoles, and methanes. It states that N-sulfonylimines have been a matter of the attention for organic chemists because sufonyl moiety activates the carbon=nitrogen (C=N) bond and hence, these compounds are used as substrates in nucleophilic additions, reactions, and Diels-Alder reactions. It mentions that imidazole derivatives show several pharmacological and biological activities and also are vital factor of lots of biologically active compounds and drugs such as losartan, eprosartan, and trifenagrel. Moreover, Lewis acidic catalysts have been used to effect the condensation of indoles with carbonyl compounds.

Saccharin sulfonic acid (SaSA) is used as a highly efficient and recyclable catalyst for the one-pot multicomponent condensation of 2-naphthol with arylaldehydes and amides (thioamides or alkyl carbamates) under green, mild (70 °C), and solvent-free conditions. In this reaction, 1-amidoalkyl-2-naphthols, 1-thioamidoalkyl-2-naphthols, 1-carbamatoalkyl-2-naphthols, bis(1-amidoalkyl-2-naphthol)s, and bis(1-carbamatoalkyl-2-naphthol)s are produced in high to excellent yields and in relatively short reaction times. Supplemental materials are available for this article. Go to the publisher's online edition ofPhosphorus, Sulfur, and Silicon and the Related Elementsto view the free supplemental file. [ABSTRACT FROM AUTHOR]

Ionic liquid triethylamine-bonded sulfonic acid ([Et 3N–SO 3H]Cl, N,N-diethyl-N-sulfoethanammonium chloride) is utilized as a highly efficient, inexpensive and homogeneous catalyst to promote the following one-pot multi-component organic transformations under solvent-free conditions: (i) the condensation of 2-naphthol with arylaldehydes and amides leading to 1-amidoalkyl-2-naphthols, (ii) the reaction of 2-naphthol with aromatic aldehydes and alkyl carbamates to produce 1-carbamatoalkyl-2-naphthols, and (iii) the condensation between 2-naphthol, arylaldehydes and thioamides leading to 1-thioamidoalkyl-2-naphthols. High yields, short reaction times, efficiency, generality, clean process, simple methodology, low cost, easy work-up, ease of preparation of the catalyst, and environmentally benign conditions are some advantages of the protocols. [ABSTRACT FROM AUTHOR]

Some new aza thia crowns were prepared. A new diester was first prepared from the reaction of α,α′-bis(bromomethyl) benzene and methylthioglycolate. Aza crowns were synthesized from the reactions of this diester and diamines (ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, and diethylenetriamine) in refluxing methanol (conventional heating) and under microwave (MW) irradiation. Based on the yields of aza crowns under these two conditions, MW irradiation is the better medium for these syntheses. [ABSTRACT FROM AUTHOR]

The article offers information on the solvent-free condensation of 2-naphthol with acetamide/urea and aromatic aldehydes to 1-amidoalkyl-2-naphthols. It mentions that the use of solvent-free reaction conditions in organic synthesis leads to remarkable decreases in reaction times, increased yields, and prevents waste, hazards, and toxicity due to solvents. It states that the condensation of 2-naphthol (2 mmol) with benzaldehyde (2 mmol) and acetamide (2.6 mmol) was chosen as a model reaction wherein its behavior was examined in the presence of different amounts of silphox and silphos under solvent-free conditions. Moreover, the promising aspects of the developed methodology are efficiency, generality, high yields, and short reaction times.

The article reports on the first catalyst-free method for 4,4-(arylmethylene)-bis(3-methyl-1-phenylpyrazol-5-ols) synthesis in a green recyclable media. It notes that the method promises high yield, efficiency, low cost, ease of product isolation, and compliance with green chemistry protocols. It discusses the development of environment-friendly syntheses including solvent application and solvent-free condition usage to achieve various chemical transformations. It considers liquid polymers or low melting point polymers as alternative green reaction media.

This article describes an efficient, simple, and clean method for the synthesis of α,α'-bis(arylidene, furylidene and cinnamylidene)cycloalkanones under solvent-free conditions. The cross-aldol condensation of cycloalkanones with aldehydes in the presence of silica-supported phosphorus pentoxide (P2O5/SiO2) or silicaphosphinoxide (silphox, [POCl3-n(SiO2)n]) as heterogeneous reagents produces the title compounds in good to excellent yields. [ABSTRACT FROM AUTHOR]

An efficient, simple, and green procedure for the synthesis of quinoxaline derivatives is described. The condensation of 1,2-diamines with 1,2-diketones using lithium bromide (LiBr) in H2O/EtOH as a green reaction media at room temperature affords the title compounds in high to excellent yields and in short reaction times.[image omitted] [ABSTRACT FROM AUTHOR]

The article presents a study wherein ionic liquid has been used successfully as accelerator for the fast synthesis of bis(indolyl)methanes via the condensation of indoles with aldehydes and ketones under solvent-free conditions at room temperature. Ionic liquid, 3-methyl-1-sulfonic acid imidazolium chloride was introduced as a novel, highly efficient and easily prepared and relatively cheap catalyst in organic synthesis. It is also mentioned that the chemicals used were purchased from Merck & Co. Inc. or Fluka Chemical Co. Thin-layered-chromatography (TLC) using silica gel SIL/UV 254 plates monitors the progress of the reactions.

Silica-supported LiHSO4 (LiHSO4/SiO2) is used as a green, cheap, and efficient catalytic system for the synthesis of bis(indolyl)methanes via the condensation of indoles with carbonyl compounds under solvent-free conditions. The reactions proceed rapidly at room temperature, and the title compounds are obtained in high to excellent yields. [ABSTRACT FROM AUTHOR]

Sulfonamides are efficiently condensed with aldehydes as well as ketones in the absence of catalyst in 1-butyl-3-methylimidazolium bromide ([bmim]Br) under microwave irradiation to afford N-sulfonyl aldimines and ketimines in good to excellent yields in short reaction times. [ABSTRACT FROM AUTHOR]

The article focuses on the method developed for N,N-dialkylsulfonamides synthesis via aza-conjugate addition reaction by microwave irradiation with potassium fluoride as an efficient and reusable reagent. It notes the significance of the N,N-Dialkyl derivatives of sulfonamides with their potential applications being an anti-ulcer, anti-emetic analgesic, and anti-inflammatory agents. It presents a table which shows the influence of rations of KF to the microwave power and substrate in the presence of tetrabutylammonium bromide (TBAB).

KF/Al2O3 efficiently catalyzes the microwave-assisted Michael addition of sulfonamides to α,β-unsaturated esters under solvent-free conditions to afford N-alkyl derivatives of sulfonamides as biologically interesting compounds in high yields and in short reaction times. In this reaction, N,N-dialkylsulfonamides are also produced, but in very low yields. [ABSTRACT FROM AUTHOR]

Zirconium tetrakis(dodecyl sulfate) [Zr(DS)4] efficiently catalyzes the synthesis of quinoxaline derivatives via the condensation of 1,2-diamines with 1,2-diketones in H2O as a green media at room temperature. Using this method, the title compounds are produced in good to excellent yields and relatively short reaction times. [ABSTRACT FROM AUTHOR]

KF/Al2O3 acts as an efficient catalytic system for the synthesis of carboacyclic nucleosides via Michael addition of pyrimidine and purine nucleobases to α,β-unsaturated esters under solvent-free and microwave conditions. Using this method, the title compounds are produced in good to excellent yields and short reaction times. [ABSTRACT FROM AUTHOR]

Silphox [POCl3-n(SiO2)n] efficiently catalyzes the condensation of benzene-1,2-diamine with mono and dicarboxylic acids under microwave irradiation to afford benzimidazole derivatives in high yields and short reaction times. [ABSTRACT FROM AUTHOR]

An efficient solvent-free procedure for the preparation of N-arylsulfonyl imines from sulfonamides and aryl aldehydes in the presence of a catalytic amount of magnesium oxide and tetrabutylammonium bromide (TBAB) under microwave irradiation is described. The advantages of this method are good to high yields, short reaction times, low cost, and matching with green chemistry protocols. [ABSTRACT FROM AUTHOR]

A very simple and efficient solvent-free method for the direct conversion of carboxylic acids to primary, secondary, tertiary alkyl, and aromatic amides in the presence of the corresponding ammonium salts, silica-supported 2,4,6-trichloro-1,3,5-triazine, and triethylamine is described. The reactions proceed rapidly at room temperature, and the products are obtained in moderate to excellent yields. [ABSTRACT FROM AUTHOR]

N‐Arylation of some pyrimidine and purine nucleobases in the presence of SiO2 and Cs2CO3 under solvent‐free as well as in solution conditions is described. In these conditions, N1‐aryl pyrimidines and N9‐aryl purines have been obtained regioselectively in moderate to high yields with relatively short reaction times. [ABSTRACT FROM AUTHOR]