Silica supported phosphorus pentoxide (P2O5·SiO2) is an efficient catalyst for synthesis of 1,3,5-substituted pyrazoles via the condensation of 1,3-diketones and hydrazines. Simplicity of procedure, mild condition, being solvent-free, high yields, and easy workup are some advantages of this protocol. Manuscript profile

Nano-silica supported boron trifluoride (BF3.SiO2) is an efficient, reusable and eco-friendly catalyst for chemoselective thioacetalization of aldehydes and ketones. So, this catalyst was applied for transthioacetalization of acetals and acylals into their corresponding 1,3-dithiolanes or 1,3-dithianes in good to excellent yields. The reactions were carried out at room temperature under solvent free and grinding conditions in 1.5-2.5 minutes. Manuscript profile

An one-pot method has been developed for the synthesis of azo dyes via sequential diazotization–diazo coupling of aromatic amines with coupling agents at room temperature in the presence of Bi(NO3)3. 5H2O. Short reaction times, high yields, a clean process, simple methodology, easy work-up and green ‎conditions are advantages of this protocol.‎ Manuscript profile

A highly efficient procedure for the preparation of N,N'-alkylidenebisamides in the presence of BF3.SiO2 as a catalyst is described. N,N'-alkylidenebisamides have been prepared via one-pot three-component condensation reaction of various aldehydes and amides. All of the reactions proceeded in high yields and in moderately short reaction times. Manuscript profile

[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. Manuscript profile

Nano-SbCl5.SiO2 and SbCl5.SiO2 are bench-top catalysts which are reusable, readily available, versatile andefficient for promotion of many acid catalyzed organic reactions. These catalysts do not need specialprecautions for preparation, handling or storage, and they can be stored at an ambient temperature for monthswithout losing their catalytic activity. 4-dihydropyrimidin-2(1H)-ones(thiones) were synthesized in thepresence of Nano-SbCl5.SiO2 or SbCl5.SiO2 as a reusable and efficient catalyst. Manuscript profile