A simple and mild method for tetrahydropyranylation of alcohols is reported at room temperature using a catalytic amount of 3-methylimidazolinium hydrogensulfate([Hmim]HSO4) as a green, efficient and reusable catalyst. Using solvent-free conditions, non-toxic and inexpensive materials, modest and clean work-up, short reaction times and high yields of the products are the advantages o...

Some 2-iminothiazolidin-4-ones have been synthesized by the reaction of dialkyl acetylenedicarboxylates with thiosemicarbazones. The reaction was performed in the presence of 10 mol% of triphenylphosphine and tetrabutylammonium bromide as a phase transfer catalyst in water as a green solvent. All the synthesized compounds were characterized by their physical and spectral data.

[B(OH)3]0.78[B(OH)2(OSO3H)]0.22 or (BSA) was simply prepared by addition of chlorosulfonic acid to commercial boric acid at room temperature. This cheap and green solid acid was used as an efficient catalyst for synthesis of acylals from aldehydes under solvent-free conditions at room temperature.

An effective one-pot synthesis of dihydropyrimidinonoes in solvent free conditions using CuCl2 as an inexpensive and readily available reagent through Biginelli condensation reaction of aldehyde derivatives, 1,3-dicarbonyl compounds and urea is described. Excellent yields, short reaction times for formation of the products and simple work-up are attractive features of this green protocol.

An efficient one-pot condensation for the synthesis of 1,8-dioxo-octahydroxanthene is  achieved through a condensation of aryl aldehydes and 5,5-dimethyl-1,3-cyclohexandione in the presence of  NBS. This method enjoys several advantages such as low cost, simple work up procedure and safe reaction condition. In addition, water was chosen as a green solvent.

the catalytic highly regio-, diastereo-, and enantioselective synthesis of a small library of spiropyrrolizidineoxindolesvia a four-component 1,3-dipolar cycloaddition reactionof azomethineylides, derived from isatin, with electron-deficient dipolarophilewas described. the process occurs at room temperature in aqueous ethanol as a green solvent and in the presence of a bidendatebis(imine)–cu(ii...

a simple and green chemical procedure was reported for the synthesis of dihydropyrimidinones from various aldehydes, ethyl acetoacetate and urea or thiourea using  holmium chloride as catalyst. the reactions were performed under solvent free conditions with ultrasound irradiation as the energy source. the advantages of this protocol include the excellent yield, operational simplicity, short tim...

cellulose was applied as a reusable and green catalyst for the facile four-component synthesis of 6-amino-4-aryl-3-methyl-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile derivatives using hydrazine monohydrate, ethyl acetoacetate, malononitrile and aryl aldehydes, under solvent-free and thermal conditions. the use of non-toxic and inexpensive catalyst, short reaction time, clean work-up and goo...

A simple, mild and high efficient procedure for one pot three component synthesis of 2-amino 4-H chromene derivatives was studied. The reaction was performed in water using aryl aldehydes, malononitrile and resorcinol, phloroglucinol or naphthole in the presence of N-methyl D-glucamine (Meglumine) as a green high efficient catalyst. The reaction was studied in thermal, microwave (MW) and ultras...

in this work, the ionic liquid triethylamine-bonded sulfonic acid {[et3n–so3h]cl}, n,n-diethyl-n-sulfoethanammonium chloride was used as a green acidic homogeneous catalyst to synthesis of 3,4-dihydropyrimidin-2(1h)-ones and 3,4-dihydropyrimidin-2(1h)-thiones as two categories of heterocycles, from aldehyde, dicarbonyl compound and urea or thiourea throughout the one-pot three components cycloc...