3,4-Dihydropyrimidinones are an important class of heterocycles due to their pharmaceutical and therapeutic properties. The most efficient method for synthesis of these 3,4-dihydropyrimidinones, first reported by Biginelli, involves three component, one-pot condensation of a β-ketoester with an aldehyde and urea under strongly acidic conditions. The major drawbacks associated with this protocol, is poor to moderate yields, when using substituted aromatic and aliphatic aldehydes. Several improved methods for this protocol have been reported, can overcome the drawback of the classical protocol. This project aims investigating tributyl hexadecyl phosphoniuom bromide(TBHDPB) as a novel and efficient catalyst for synthesis of 3,4dihydropyrimidinones/thiones in milder reaction conditions. Optimization of the reaction conditions was attempted. The effect of temperature and solvent was studied. The best results were obtained in ethanol at 80 oC. The best catalytic activity of TBHDPB was optimized to be 10 mol% ( 0.1 mmol , 0.051g). Under optimal conditions, all reactions were completed within 45-80 min. All pure products were obtained in excellent yields (60-90%). The products were characterized by comparison of melting points and 1HNMR with those prepared in accordance with the literature procedures. The remarkable advantages of the present methodology over the literatures method, including the easily and inexpensive available catalyst, simple experimental procedures, shorter reaction times, excellent yields, easy work up and purification of products by non-chromatographic methods. پرونده مقاله

1,4-bis(triphenyl phosphonium)butane peroxodisulfate(BTPPBPDS) were synthesized by treating 1,4-bis(triphenyl phosphonium)butane dibromide and potassium peroxydisulfate in aqueous solution.This was used mild and efficient reagent for oxidation of alkyl benzenes to their corresponding carbonyl compounds in very good to high yields. پرونده مقاله

Put the peroxodisulfate ion (S2O82-) in the phase transfer catalyst banzyltriphenylphosphonium can make a catalyst with mild oxidation property, and used it for oxidation of Benzylhalides to corresponding Benzylaldehyde Compounds. For making catalyst used xylene and water as solvent, and it was an easy process with high yield. Oxidation used in reflux condition with acetonitrile as solvent. The advantages of this oxidation: high yield and short time پرونده مقاله

A Simple and efficient method for Michael addition of pyrrole and indole to α,β- un saturated compounds has been developed in the presence of oxalic acid under refluxing reaction condition was achieved. پرونده مقاله

Put the peroxodisulfate ion (S2O82-) in the phase transfer catalyst banzyltriphenylphosphonium can make a catalyst with mild oxidation property, and used it for oxidation of Benzylhalides to corresponding Benzylaldehyde Compounds. For making catalyst used xylene and water as solvent, and it was an easy process with high yield. Oxidation used in reflux condition with acetonitrile as solvent. The advantages of this oxidation: high yield and short time. پرونده مقاله

This study reports a new methodology for the efficient synthesis of trisphenol compounds using the reaction of 2,6-bis(hydroxymethyl) phenols with phenols under heterogeneous conditions. A sulfonated reduced graphene oxide (RGO-SO3H) nanocatalyst was used to promote the reaction under solvent-free conditions. A range of trisphenol compounds were produced in the presence of this catalyst system in good to excellent yields. In the presence of this catalyst system, a less amount of phenol is required, which improves the environment through its capability in synthesis of trisphenols. The RGO-SO3H catalyst was reusable at least for 8 times in this process without a significant decrease in its catalytic activity. پرونده مقاله

Si-Im/HSO4(1-methyl-3-(3-(trimethoxysilyl) propyl) imidazolium hydrogen sulphate functionalized Copper oxide nanoparticles(CuO NPs )as a novel supporting ionic liquid was prepared and characterized by FT-IR spectroscopy, FE-SEM, XRD, TGA, and EDX techniques. It was used as a recyclable catalyst for the one-pot, three-component synthesis of 1, 4- dihydro Pyrano [2, 3-c] pyrazoles derivatives. The results showed that the catalyst was very efficient, and in addition, at the end of the reaction the catalyst could be easily isolated and reused for the next reaction without any appreciable loss of its catalytic activity. The reused catalyst was also characterized by the FE-SEM and EDX techniques. پرونده مقاله