A direct and an efficient conversion of a wide range of primary, secondary even tertiary alcohols to the corresponding iodides have been achieved under ionic liquid conditions. The method involves preparation of ionic liquid-based iminium chloride intermediate from DMF-like ionic liquid then stirring it with alcohol in present of sodium iodide. The higher yields of […]
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 […]
An efficient synthesis of polyhydroquinoline derivatives was reported via four-component coupling reactions of aldehydes, 1,3-dicarbonyl ketones (dimedone or 1,3-cyclohexanedione), ethyl acetoacetate or methyl acetoacetate and ammonium acetate in the presence of a catalytic amount of nanocrystalline TiO2 under solvent free conditions. The reported method is mild, rapid and has the advantages such as heterogeneous catalysis, […]
A comparison of the photoefficiency of Ni(II) and NiS incorporated into zeolite P towards photodecolorization of Eriochrome Black T dye solution was investigated in a photocatalytic reactor using UV lamp as a light source. The effect of various experimental variables on the decolorization performance of the process was evaluated by examining catalyst dosage, temperature, initial […]
A convenient and efficient procedure for the synthesis of 14-aryl or alkyl-14H-dibenzo[a,j]xanthenes by condensation of 2-naphthol and aldehydes in the presence of Methylimidazolium hydrogensulfate, as a Brönsted acidic ionic liquid ([Hmim]HSO4), is described. Both aromatic and aliphatic aldehydes reacted easily to afford the corresponding 14-aryl or alkyl-14H-dibenzo[a,j]xanthenes in good yields under solvent-free conditions. Moreover, the […]
Tetrahydropyranylation of alcohols and phenols, acetylation of aldehydes and N-Boc protection of amines are efficiently catalyzed by melamine trisulfonic acid (MTSA). All reactions were performed at room temperature in good to high yields.
The aerobic oxidation of alcohols was efficiently completed in high conversion and selectivity using Cu3/2[PMo12O40]/SiO2 as catalyst under mild reaction condition. This reaction provides a new environmentally friendly rout to the conversion of alcoholic function to carbonyl groups.
A facile and efficient method for the preparation of 1,1-diacetates of aldehydes is improved. The acidified kaolin with sulfuric acid (2 % w/w) catalyzed 1,1-diacetates formation from aldehydes in solvent-free conditions. Both aromatic and aliphatic aldehydes gave high yields (85-95 %) of the corresponding 1, 1-diacetates. Advantages of this method are the use of inexpensive […]
1,1’-(Ethane-1,2-diyl)dipyridinium bistribromide (EDPBT) was used as a chemoselective and effective organocatalyst for the silylation of hydroxyl groups as well as desilylation of trimethylsilyl ethers under mild conditions at room temperature with good to excellent yields.
The esterification of free fatty acids (FFA) with methanol is studied using Sulfonated Porous Carbon (SPC) as catalyst. In compare to the amorphous sugar catalyst and protonated Nafion, the proposed catalyst shows stability and high efficient performance in biodiesel production. The highest initial rate of oleic acid conversion is obtained at catalyst loading of 1 […]
