Sodium Dihydrogen Phosphate as an Efficient Catalyst for One-Pot, Three-Component Synthesis of α-Aminophosphonates Under Solvent-Free Conditions at Room Temperature

One-pot synthesis of β-acetamido ketones using boric acid at room temperature

β-acetamido ketones were synthesized in excellent yields through one-pot condensation reaction of aldehydes, acetophenones, acetyl chloride, and acetonitrile in the presence of boric acid as a solid heterogeneous catalyst at room temperature. It is the first successful report of boric acid that has been used as solid acid catalyst for the preparation of β-acetamido ketones. The remarkable advantages offered by this method are green catalyst, mild reaction conditions, simple procedure, short reaction times, and good-to-excellent yields of products.

A facile synthesis of new 2-amino-4H-pyran-3-carbonitriles by a one-pot reaction of α, α'-bis(arylidene) cycloalkanones and malononitrile in the presence of K2CO3

A rapid and environmentally friendly method is developed for the synthesis of a series of new substituted 2-amino-4H-pyran-3-carbonitriles through a one-pot condensation of malononitrile and α, α′-bis(arylidene) cycloalkanones in ethanol by using K₂CO₃ as a catalyst. Short experimental reaction times, excellent yields, no need to use cumbersome apparatus for purification of the products, and inexpensiveness and commercially availability of the catalyst are the advantages of this method.

Tris(Hydrogensulfato)Boron Catalysed Rapid Synthesis of 2-Substituted-2,3-Dihydroquinazolin-4(1H)-Ones under Solvent-Free Conditions

Aldehydes or ketones react readily in one-pot with isatoic anhydride and ammonium salts in the presence of tris-(hydrogensulfato)boron to produce the corresponding 2,3-dihydroquinazolin-4(1 H)-ones in high yields under solvent-free conditions. The use of tris(hydrogensulfato)boron makes this process quite simple, more convenient and environmentally friendly. 2,3-Dihydroquinazolin-4(1 H)-one derivatives have interesting biological and pharmacological activities.

A highly efficient bismuth salts-catalyzed route for the synthesis of α-aminophosphonates

A convenient synthesis of different types of α-amino phosphonates via one-pot solvent-free three component reactions of aldehydes, amines and phosphites catalyzed by bismuth salts has been investigated. Bismuth triflate is found to be the most effective catalyst for this reaction.