Manas M. Sarmah

Microwave-Promoted Catalyst- and Solvent-Free Aza-Diels–Alder Reaction of Aldimines with 6-[2-(Dimethylamino)vinyl]-1,3-dimethyluracil

A microwave-promoted aza-Diels-Alder reaction between 6-[2-(dimethylamino)vinyl]-1,3-dimethyluracil and aldimines has been developed for the construction of dihydropyrido[4,3-d]pyrimidines. Urea is effectively employed as an environmentally benign source of ammonia in the absence of any catalyst or solvent. The key step in the reaction is in situ generation and trapping of the reactive aldimine formed from urea and aldehyde by the diene system of the uracil. The reaction is clean, and excellent yields are obtained in a matter of a few minutes.

Exploration of uracils: pot and step economic production of pyridine core containing templates by multicomponent aza-Diels–Alder reaction

An efficient pot and step economic protocol for synthesis of pyrido[2,3-d]pyrimidine derivatives from a multicomponent aza-Diels–Alder reaction of uracil analogues, aromatic aldehydes and acetophenones in the presence of Na2CO3 in DMF was developed. The key step of the reaction is in situ generation of the reactive dienophile from aldehyde and acetophenone and their subsequent reaction with diene to give the desired product.

Indium-catalyzed microwave-accelerated pot economic C–C bond formation process towards the ‘dry-media’ synthesis of pyrimidine derivatives

An efficient pot and time economic ‘dry-media’ synthesis of pyrimidine core containing scaffolds by application of an indium triflate catalyzed carbon–carbon bond formation procedure through Diels–Alder reaction using microwaves is described. The method is associated with some attractive characteristics such as short reaction time, high yield of products, and recyclability of recovered catalyst from the reaction mixture.

Ultrasound mediated efficient synthesis of spironaphthoquinolines

An atom-economical synthesis of spironaphthoquinolines from a mixture of 2-aminoanthracene, aldehyde and a Knoevenagel condensation product was developed. The association of the method with the use of ultrasound and its procedural simplicity makes it an attractive protocol for the formation of novel and important heterocycles.