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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.

The Biginelli-type compounds 4,5,8a-triarylhexahydropyrimido[4,5- d ]pyrimidine-2,7(1 H ,3 H )-diones were synthesized by a one-pot three-component reaction using sulfated tin oxide as a reusable catalyst. This method has the advantages of high yields, short reaction time, simple starting materials and reusability of catalyst for several times.

An efficient asymmetric synthesis of homoallylic alcohols is described by the allylation of carbonyl compounds using organocatalysts as chiral directors in the presence of tin metal. The effect of chiral environment is also studied on the allylation reactions. This method allows us to obtain two different enantiomers of homoallylic alcohol in the presence of the corresponding chiral compound. The protocol is applied to various aldehydes to obtain high yields and excellent enantioselectivities for the corresponding homoallylic alcohols.

3-Chlorophenylboronic acid promotes efficient synthesis of 3-substituted indole derivatives via aza-Friedel–Crafts reaction of indoles, aromatic aldehydes, and N,N-dimethylaniline at room temperature. The mild reaction conditions, excellent yields, and easy experimental workup are striking features of this procedure for synthesis of 3-substituted indoles.

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.

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 %).

We have developed an efficient protocol for the synthesis of $$\upbeta $$ -amino carbonyl compounds using phenylboronic acid as effective and eco-friendly catalyst via one-pot three-component Mannich reaction. Excellent yields, mild reaction condition, and simple experimental work-up procedure are some of the advantages of this method, which makes it a useful protocol for the synthesis of $$\upbeta $$ -amino carbonyl compounds.

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.

A convenient protocol has been developed for the synthesis of Baylis–Hillman adducts in the presence of a base and an organocatalyst. We have designed and synthesized organocatalysts based on hydrogen bonding using a pyrrolidine ring as the backbone and applied them to Baylis–Hillman transformations. This method provides products in good to high yields (73–90%) and with excellent enantiomeric excesses (up to 96%) and reasonable reaction times.

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.

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.

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 %).

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.

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.

We report an enantioselective Henry (nitroaldol) reaction catalysed by an organocatalyst using water as solvent. The enantioselective synthesis of β-nitroalcohols was achieved by using a neutral chiral organocatalyst, through strong hydrogen bonding, which results in the formation of corresponding products in excellent yield and enantioselectivity at room temperature. Other attractive features of the method are the eco-friendly, non-hazardous, and mild reaction conditions, inexpensive catalyst, and simple work up conditions.