Search

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.

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 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.

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.

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

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 %).