Montmorillonite KSF Clay Research Articles

Montmorillonite KSF clay-promoted synthesis of enantiomerically pure 5-substituted pyrazoles from 2,3-dihydro-4 H-pyran-4-ones

2,3-Dihydro-4 H-pyran-4-ones derived from d-glucal undergo rapid condensation with aryl hydrazines in the presence of montmorillonite KSF clay under mild conditions to afford a novel class of chiral 5-substituted pyrazoles in good yields with high selectivity. The stereochemical assignments of the products were achieved by NMR studies.

Montmorillonite KSF Clay Catalyzed One‐Pot Synthesis of α‐Aminonitriles.

Aryl imines, formed in situ from aldehydes and amines undergo smoothly nucleophilic addition with trimethylsilyl cyanide on the surface of montmorillonite KSF clay under mild reaction conditions to afford the corresponding α-aminonitriles in excellent yields. The solid acid can be recovered and recycled in subsequent reactions with a gradual decrease of activity.

Montmorillonite clay catalyzed alkylation of pyrroles and indoles with cyclic hemi-acetals

Cyclic hemiacetals such as 2-deoxy- d-ribose and 2-deoxy- d-glucose react smoothly with pyrroles and indoles on the surface of montmorillonite KSF clay under extremely mild reaction conditions to afford optically active di-pyrrolyl and bis-indolyl alkanols in good yields with high selectivity.

Montmorillonite KSF clay catalyzed one-pot synthesis of α-aminonitriles

Aryl imines, formed in situ from aldehydes and amines undergo smoothly nucleophilic addition with trimethylsilyl cyanide on the surface of montmorillonite KSF clay under mild reaction conditions to afford the corresponding α-aminonitriles in excellent yields. The solid acid can be recovered and recycled in subsequent reactions with a gradual decrease of activity.

Investigation of the Montmorillonite clay-catalyzed [1,3] shift reaction of 3-methyl-2-butenyl phenyl ether

The [1,3] shift reaction of 3-methyl-2-butenyl phenyl ether was catalyzed more effectively by Montmorillonite K10 clay than Montmorillonite KSF clay, and proceeded with greatest ortho-selectivity in carbon tetrachloride at room temperature.

A Convenient and Selective Method for Preparation of Enol Acetates from Ketones Using Montmorillonite KSF Clay.

The reaction of ketones with stoichiometric amounts of acetic anhydride and Montmorillonite KSF clay at room temperature afforded the corresponding enol acetates in excellent yields. It has also been observed that by performing the reactions under microwave irradiation the reaction time can be dramatically reduced.

Clay Catalysed Synthesis ofDihydropyrimidinones under Solvent-free Conditions

A fast and high yielding one-pot synthesis of 3,4-dihydropyrimidin-2(1H)-ones from β-keto esters, urea and various aliphatic and aromatic aldehydes using montmorillonite KSF clay as a catalyst in solvent-free condition under microwave irradiation is described. The catalyst can also be recycled in these syntheses.

A CONVENIENT AND SELECTIVE METHOD FOR PREPARATION OF ENOL ACETATES FROM KETONES USING MONTMORILLONITE KSF CLAY

ABSTRACT The reaction of ketones with stoichiometric amounts of acetic anhydride and Montmorillonite KSF clay at room temperature afforded the corresponding enol acetates in excellent yields. It has also been observed that by performing the reactions under microwave irradiation the reaction time can be dramatically reduced.

Multicomponent reactions under clay catalysis

Three-component reactions for the synthesis of substituted dihydropyrimidines ( 4), chromenes ( 8) and tetrahydroquinolines ( 11) have been performed in water and in the presence of a montmorillonite KSF clay. The products, easily isolated from the reaction mixture by crystallisation, are obtained in high yield and selectivity and the catalyst can be recycled for many runs without losing its activity.

Regeneration of Aldehydes from Bisulfite Addition Products in the Solid State using Montmorillonite KSF Clay under Microwave Irradiation

Microwave irradiation of bisulfite addition products with montmorillonite KSF clay under solvent-free conditions provides a fast, efficient and simple method for regeneration of aldehydes in excellent yields.

Regeneration of Aldehydes from Bisulfite Addition Products in the Solid State using Montmorillonite KSF Clay under Microwave Irradiation

Microwave irradiation of bisulfite addition products with montmorillonite KSF clay under solvent-free conditions provides a fast, efficient and simple method for regeneration of aldehydes in excellent yields.