Metal Hydrogen Sulfates Research Articles

A reactive and environmentally friendly protocol for expeditious synthesis of various resorcinarenes using zinc hydrogen sulfate

ABSTRACTIn this work, for the first time, metal hydrogen phosphates and sulfates have been studied as effective solid acid catalysts for the condensation of resorcinol with aromatic and aliphatic aldehydes to give tetrameric cyclic products, resorcinarenes, which have major roles in biological and industrial activities. This catalyst has several advantages, it is non-toxic, thermally and mechanically stable, inexpensive and highly resistant against organic solvents. It increases the reaction rate about six fold and makes this method an attractive alternative to the existing methods for resorcinarene formation. Interestingly, the present catalyst exhibited a high turnover number (TON) and turnover frequency (TOF) which were even comparable with that of HCl.

Zinc Hydrogen Sulfate Promoted Multi-component Preparation of Highly Functionalized Piperidines

The preparation of substituted piperidines via three-component reaction between aldehydes, aromatic amines and acetoacetic esters has been developed. The process has been carried out under ambient conditions in the presence of zinc hydrogen sulfate [Zn(HSO4)2]. A variety of aldehydes and amines were yielded into the corresponding products demonstrating the versatility of the reaction. Keywords: Diastereoselectivity, functionalized piperidines, metal hydrogen sulfate, zinc hydrogen sulfate [Zn(HSO4)2], Donepezil, Sertindole, Risperidone, anti-inflammatory, anti-hypertensive, anti-convulsant

ChemInform Abstract: Catalytic and Efficient Oxidation of Urazole Derivatives to Their Corresponding Triazolinediones Using Ammonium Nitrate and Metal Hydrogen Sulfate as Catalyst.

AbstractAdvantages are high selectivity, cost‐efficiency, and easy work‐up.

Discussion of unusual hydrogen atom display in solid acids

Studying crystal structures of superprotonic phases of alkali metal hydrogen sulfates and selenates, a very unusual phenomenon has been revealed. Dynamically disordered hydrogen atoms with low position occupancies are clearly seen in corresponding electron density maps. To explain this effect, an idea about a new type of twinning, dynamic twinning, was proposed and discussed.

Catalytic and Efficient Oxidation of Urazole Derivatives to Their Corresponding Triazolinediones Using Ammonium Nitrate and Metal Hydrogen Sulfate as Catalyst

AbstractCatalytic oxidation of a variety of urazoles to the triazolinediones via combination of NH4NO3 in the presence of a catalytic amount of aluminium hydrogen sulfate has been developed at room temperature in dichloromethane.

ChemInform Abstract: A Novel and Efficient Solvent‐Free and Heterogeneous Method for the Synthesis of Primary, Secondary and Bis‐N‐acylsulfonamides Using Metal Hydrogen Sulfate Catalysts.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Al(HSO 4) 3/silica gel as a novel catalytic system for the ring opening of epoxides with thiocyanate anion under solvent-free conditions

For the first time, metal hydrogen sulfates and phosphates/silica gel have been studied as efficient and powerful solid acid catalysts in the ring opening of epoxides with thiocyanate anion. The most significant result was obtained by Al(HSO 4) 3/SiO 2 which afforded the corresponding β-hydroxy thiocyanates under mild reaction conditions and in very short reaction times. The cheapness, availability of the catalyst, ease of procedure and work-up make this method attractive for the organic synthesis.

A novel and efficient solvent-free and heterogeneous method for the synthesis of primary, secondary and bis- N-acylsulfonamides using metal hydrogen sulfate catalysts

Some metal hydrogen sulfates were used as acid catalysts in the N-acylation of different sulfonamides using carboxylic acid chlorides and anhydrides as acylating agents under both heterogeneous and solvent-free conditions. Al(HSO 4) 3 and Zr(HSO 4) 4 were found to have the highest activity and catalyze the reactions efficiently to furnish the primary N-acyl sulfonamides (RCONHSO 2R′), secondary N-acylsulfonamides (RCONR″SO 2R′) and bis- N-acylsulfonamnides [RCO(SO 2R′)N-R″-N(SO 2R′)COR] in good to high yield. The mild reaction conditions, inexpensive and low toxicity of catalysts and easy work-up procedure make this method attractive.

Metal Hydrogen Sulfates M(HSO4)n: As Efficient Catalysts for the Synthesis of Quinoxalines in EtOH at Room Temperature

AbstractA convenient method for the synthesis of quinoxalines catalysed by metal hydrogen sulfates by the reaction of 1,2‐diamino compounds and 1,2‐dicarbonyl compounds in ethanol as solvent at room temperature is reported.

M(HSO4)n-Promoted Synthesis of 2-Aryl-1-arylmethyl-1H-1,3-benzimidazole Derivatives

We have developed a highly selective synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzimidazoles from the reaction of o-phenylenediamines and aromatic aldehydes in the presence of metal hydrogen sulfates [M(HSO4)n] in water and also under solvent-free conditions in good to excellent yields.

Applications of Some Metal Hydrogen Sulfates in Organic Transformations

Sodium, magnesium, ferric, zirconium and aluminum hydrogen sulfates have been used as efficient reagents in organic chemistry. A broad range of reactions including deprotection, oxidation, C-C, C-N and C-O bond formation and cleavage took place in the presence of these reagents under mild and completely heterogeneous reaction conditions in good to high yields. In many cases the reagents were recycled and reused. Keywords: Bromination, Oxidation reactions, Magnesium hydrogen sulfate, Carbon-Oxygen Bonds, Nitrosation

Friedländer Quinoline Synthesis Catalyzed by M(HSO4)n (M=Al, Mg, Ca) under Solvent-Free Conditions

Polysubstituted quinolines were synthesized from the 2-aminobenzophenone, ethylacetoacetate or ketones in the presence of metal hydrogen sulfates [M(HSO 4 ) n ] in good to high yields at 70 °C under solvent-free conditions.

Metal Hydrogen Sulfates Catalyzed Methoxymethylation of Alcohols under Solvent‐Free Conditions

AbstractMethoxymethylation of a variety of alcohols was performed by using formaldehyde dimethoxy acetal in the presence of metal hydrogen sulfate M(HSO4)n at room temperature and solvent‐free conditions. The methoxymethyl ethers (MOM‐ethers) were obtained with high yields and purity.

Efficient Synthesis of 3,4-Dihydropyrimidin-2(1H)-one Using Metal Hydrogen Sulfates M(HSO4)n as Catalyst under Solvent-Free Conditions

Abstract Metal hydrogen sulfates M(HSO 4 ) n (Ca(HSO 4 ) 2 , Zn(HSO 4 ) 2 , and oxone®) were used to catalyze one-pot three-component condensation reactions of aldehydes, 1,3-dicarbonyl compounds, and urea at 90°C under solvent-free conditions to give 3,4-dihydropyrimidin-2(1 H )-one in high yields.

Preparation of indolylmethanes catalyzed by metal hydrogen sulfates

Solid acids were developed and applied to the condensation reactions of indole with carbonyl compounds at ambient temperature. Tetra-(indolyl)methanes were obtained by the condensation reaction of indole with dialdehyde compounds.

Atomic level mechanism of proton transport in alkali metal hydrogen sulfate and selenate superionic conductors

The mechanism of proton diffusion in alkali metal hydrogen sulfates and selenates is analysed. The latest X-ray diffraction investigations of these compounds show that a highly correlated dynamic disorder of the hydrogen bonds occurs in the superionic phases. The observed diffraction patterns result from dynamically twinned crystals, which consist of a symmetry-related number of domains. We discuss the ‘anomalous display of the dynamically disordered hydrogen atoms on the electron density maps’, which is observed in the superionic phases. New X-ray diffraction data allow the atomic level mechanism of proton transport in the alkali metal hydrogen sulfates and selenates to be elucidated in detail.

ChemInform Abstract: Synthesis, Structure and Thermal Behavior of Two‐Valent Metal Hydrogen Sulfates.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.