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In present work, we have described the use of polyamine solid supported GN3 as catalyst in organic transformations using 1H-indole-3-carbaldehyde. To the best of our knowledge, reports for the synthesis of chromen substituted at 3C position of indole are extremely rare in the literature. The polyamine functionalized immobilized silica (GN3) was found to be an excellent catalyst for synthesis of novel 2-amino-4-(1H-indol-3-yl)-5-oxo-4,5-dihydropyrano[3,2-c]chromene-3-carbonitrile derivatives and Knoevenagel condensation. Catalyst GN3 was able to furnish excellent yield for a wide range of products. Moreover, the catalyst was reusable and reused for several times without loss of its catalytic activity.

Both enantiomers of the title compounds can be obtained by a simple change in the ligand structure under otherwise identical conditions.

Sulfated tin oxide is found to be an efficient catalyst for the one-pot three-component reaction of aromatic aldehydes, aromatic ketones and urea to give the title compounds (IV) in good yields, in general.

Phospha—Michael addition of P(O—Et)3 to benzylidenemalononitriles (I) in the presence of a proline-based organocatalyst represents one of the most straightforward routes for the synthesis of optically active β-malonophosphonates (III) (13 examples).

This present method deals with an exceedingly rare aspect of α-aminophosphonate synthesis. We studied an enantioseletive one-pot synthetic method for the syntheses of optically active α-aminophosphonates by employing an organocatalyst. Some new organocatalysts were synthesized and studied for their reactivity and enantioselectivity. The organocatalyst effectively catalyzed the reaction and provided the corresponding α-aminophosphonates in high yields (71–90 %) with excellent enantiomeric excess values (73–92 %).

A novel and eco-friendly method for the asymmetric Henry reaction of aldehydes is developed.

An efficient protocol was developed for the synthesis of 3-aminoalkylated indoles using 3-chlorophenylboronic acid as a catalyst under ambient temperature conditions. The three-component reaction of indoles, aromatic aldehydes and N -methyl aniline offered corresponding 3-aminoalkylated indoles in excellent yields. This protocol presents some remarkable features such as mild reaction conditions, simple workup procedure and excellent yields.

A series of new organocatalysts is designed based on hydrogen bonding motifs and applied to the title reaction.

An efficient synthesis of dicycloalkenopyridines was achieved via one-pot three-component condensation of aromatic aldehyde, cyclohexanone, and hydroxylamine hydrochloride using 3-nitrophenylboronic acid as an efficient catalyst under ambient condition. The current methodology offers several advantages such as high yields (78–90%) and simple experimental work-up at ambient temperature conditions.

PTF is found to be the catalyst of choice for the direct asymmetric aldol reaction of cyclohexanone with aromatic aldehydes to yield the adducts with (nearly) complete diastereoselectivity and good enantioselectivity under optimized conditions.