A convenient, one-pot method for the synthesis of diazonium salt has been developed by the sequential diazotization of aromatic amines with NaNO2, polymer- supported periodic acid (PPIA) and 2-naphthole under solvent-free conditions at room temperature. By using this method, several types of aromatic amine, containing electron-withdrawing and electron-donating groups, were rapidly converted to the corresponding […]
Molybdate sulfuric acid (MSA) has been prepared and used as catalyst for the Biginelli synthesis of some quinazolinones/thiones under solvent-free conditions. The catalyst loading is low and it shows recyclability. This method has advantages such as avoidance of the organic solvents, high yield of pure products, short reaction times and operational simplicity.
[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.
The ionic liquid Li(OHCH2CH2NH2)(CF3OAC) was found to efficiently catalyze the three-component reaction between different enols, aldehydes, and malononitrile , leading to rapid synthesis of 2-amino-4H-chromene derivatives in fairly high yields. The catalyst is easily prepared, highly stable, simple to handle and recycled for several times without significant loss of activity. The method is simple, starts […]
ZrP2O7 nanoparticles (NPs) as an efficient catalyst have been used for the preparation of 1,6-diamino-2- oxo-4-phenyl-1,2-dihydropyridine-3,5-dicarbonitrile derivatives via one-pot coupling of hyrazine hydrate, ethyl cyanoacetate, malononitrile and aromatic aldehydes under reflux conditions in ethanol. Using this method we obtained low reaction times, easy isolation of the targeted molecules, excellent yields.
Michael addition of pyrimidine and purine nucleobases to substituted as well as unsubstituted α,β-unsaturated esters efficiently proceeds in the presence of catalytic amount of zinc oxide in ionic liquid 1-butyl-3-methylimidazolium bromide (ZnO/[bmim]Br) under microwave irradiation to afford carboacyclic nucleosides, as biologically important compounds, in good to excellent yields and in short reaction times.
An efficient synthesis of polyhydroquinoline derivatives is achieved via Hantzsch condensation reaction between aldehydes, dimedone, ethyl acetoacetate and ammonium acetate in the presence of catalytic amount of SFHS in ethanol. This method gives remarkable advantages such as shorter reaction time, simple workup procedure and good to excellent yields. Furthermore the catalyst can be recovered conveniently […]
A convenient synthesis of different types of polyfunctional dihydropyrrol-2-ones via one-pot four component reactions of formaldehyde, dialkyl acetylenedicarboxylates and amines, catalyzed by trichloroacetic acid (Cl3CCO2H) at room temperature has been investigated. The significant advantages of this synthetic method are mild reaction conditions, available and inexpensive material, short reaction times, good yields, simple work-up.
The ionic liquid, N,N,N,N-tetramethylguanidiniumtriflate (TMGTf) was found to be an efficient catalyst solvent for Henry reaction between nitromethane and isatin derivatives to provide 3-hydroxy-3-(nitromethyl)indolin-2-one under mild conditions. The ionic liquid amenable to successive recycling without appreciable decrease in activity. Synthesized compounds have been screened for their anti-diabetic activity.(The ionic liquid, N,N,N,N-tetramethylguanidiniumtriflate (TMGTf) was found to […]
A new dimeric orthopalladated complex was synthesized via reaction of 2,3-dimethoxy benzaldehyde oxime with palladium chloride and lithium chloride in methanol as solvent and sodium acetate as base at room temperature. The catalytic activity of this dimeric [Pd{C6H2(-CH=NOH)-(OMe)2-2,3}(µ-Cl)]2 complex as an efficient, air, and moisture tolerant catalyst was investigated in Mizoroki–Heck cross coupling reaction of […]