The asymmetric direct vinylogous Michael reaction of α,β-unsaturated γ-butyrolactams with alkylidene malonates has been developed. Various 5-substituted 3-pyrrolidin-2-ones were obtained in high yields (up to 93%) with excellent stereoselectivities (up to 94% ee, 95 : 5 dr), using a novel bifunctional C(1)-symmetric guanidine organocatalyst embodied a secondary amine subunit.

A water soluble, Bronsted acid, 5-sulfosalicylic acid as an efficient organocatalyst was used for the synthesis of physiologically active 2-substituted benzimidazole derivatives from o-phenylenediamine and aromatic aldehydes in ethanol at reflux condition. Cost-effectiveness, use of non-hazardous solvents, metal free and commercially available catalyst, single-step, environmentally fri...

This work describes catalytic and asymmetric aziridinations (15 examples, 95-98% ee) of benzyl bromide and imines via the imino Corey-Chaykovsky reaction using (thiolan-2-yl)diarylmethanol benzyl ether as an organocatalyst. The catalyst and analogues thereof were prepared through an expeditious and efficient synthetic route featuring a double nucleophilic substitution and Shi epoxidation as key...

A conceptually novel nanoparticle-supported and magnetically recoverable organocatalyst has been developed, which is readily prepared from inexpensive starting materials in a truly sustainable manner; which catalyzes the Paal-Knorr reaction with high yield in pure aqueous medium that avoids the use of toxic organic solvents, even in the workup step.

The first enantioselective catalytic 1,2-hydroperoxidation has been achieved in the presence of PEG-600 using an acid-base bifunctional chiral squaramide as the organocatalyst, affording a range of enantioenriched α-N-substituted hydroperoxides bearing an oxindole moiety with excellent stereoselectivities (up to 99% ee).

Acrylic esters, thioesters and N-acryloyl pyrrole have been identified as effective electrophiles in the enantioselective Michael addition reaction with beta-keto ester pro-nucleophiles catalysed by a cinchona alkaloid derived bifunctional organocatalyst; enantiomeric excesses of up to 98% and yields of up to 96% can be obtained for a range of Michael acceptors and pro-nucleophiles.

Reduced graphene oxide (rGO) has been used as a support for piperazine to provide a heterogeneous bifunctional organocatalyst (rGO-NH) that is able to efficiently promote vintage organic transformations such as Knoevenagel, Michael and aldol reactions. The obtained results suggest a significant role of the support in the course of these reactions.

1,2-Disubstituted-3,4-dihydronaphthalenes could be conveniently synthesized with high yields by the cycloaddition reactions of easily available vinylarenes with electron-deficient alkynes such as dimethyl, or diethyl acetylenedicarboxylate, methyl phenylpropiolate in the presence of DMF.DMA (N,N-dimethylformamide dimethyl acetal) as organocatalyst.

A new method for the synthesis of pyran fused coumarins by 3-bromo-4-hydroxycoumarins as cyclic α-halo ketones based on an organocatalyst assisted three-component tandem reaction is investigated. To the best of our knowledge, cyclic α-halo ketones have not yet been used for the synthesis of pyran fused coumarins.