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Method describes asymmetric reaction of triethyl phosphites and 2-arylidenemalononitrile catalysed by the chiral organocatalyst in solvent ethanol. The organocatalyst effectively catalyse reaction to give β-malonophosphonates in high yields (85–64%) and good to moderate enantiomeric excess (78–53%).

An efficient synthesis of 2-amino-4H-chromene derivatives is achieved via one pot three component coupling reaction of aromatic aldehyde, active methylene compound and activated phenol in presence of silica gel supported polyamine heterogeneous catalyst. The catalyst is easily prepared, highly stable, simple to handle and recycled for several times without significant loss of activity.

Phenylboronic acid has been found to be an efficient catalyst for the synthesis of 1,5-benzodiazepine derivatives via cyclocondensation of o-phenylenediamine and various ketones in good to excellent yields (82–91%) using acetonitrile as solvent at reflux condition. The remarkable advantages offered by this method are easy mild reaction condition, experimental work up and good to excellent yields of products.

A simple, inexpensive and efficient one-pot synthesis of piperidine derivatives was achieved in excellent yield via the three-component reaction of substituted aniline, 1,3-dicarbonyl compound and aromatic aldehyde using phenylboronic acid as catalyst.

Some new aldimines were synthesized from substituted 2-amino thiazoles and different aromatic aldehydes usingL-proline as an efficient catalyst. The structure elucidation of aldimines has been made on the basis of elemental analysis and spectral data. The easy work up, higher yield and shorter reaction time are the advantages of the method.