a practical and new method for the synthesis oxindole substituted pyrrolo[2,3-d]pyrimidines by the condensation of isatin, acetophenone and 6-amino-uracil under ultrasound irradiation conditions at 60 °c was described. the reaction was developed via a sequential tandem process to afford the oxindole substituted pyrrolo[2,3-d]pyrimidines in good to excellent yields. all reactions performed effic...

poly (n-bromosuccinimide) (pnbs) as a mild, efficient, non-acidic, polymeric and heterogeneous catalyst was applied for simple conversion of epoxides into thiiranes by treatment with kscn or (nh2)2cs at room temperature. aliphatic and aromatic epoxides converted into their corresponding thiiranes under mild conditions. all reactions proceeded in short reaction times and afforded the correspondi...

stable crystalline phosphorus ylides are obtained in excellent yields from the 1:1:1 addition reactionbetween hydantoins or thiohydantoins and dialkyl acetylenedicarboxylates in the presence oftriphenylphosphine. these phosphoranes undergo smooth intramolecular wittig reaction followedby an electrocyclic ring opening to produce dialkyl (e)-2-(2,5-dihydro-5,5-diaryl-2-thioxo-1h-imidazol-4-yl)fum...

the three components one pot synthesis of 2-amino-4h-benzo-[b] -pyran derivatives were obtained in good to excellent yields within short reaction time by condensing dimedone, aldehydes and malanonitrile or ethylcyanoacetate using a catalytic amount of (diacetoxyiodo)benzene as hypervalent iodine in aqueous ethanol under reflux conditions have been discussed. this aqua mediated knoevenagel-cyclo...

Highly substituted 1,4-dihydropyrano[2,3-c]pyrazole derivatives were synthesized by four-component reaction of aromatic aldehydes, malononitrile, ethyl acetoacetate and various phenylhydrazine, using nickel ferrite as a recyclable nanocatalyst by a grinding method under solvent-free and thermal conditions. The reaction has the advantages of good yields, less pollution, ease of separation of the...

Two highly efficient protocols for the production of bis-coumarins under solvent-free conditions have been introduced. The reaction of 4-hydroxycoumarin (2 eq.) with arylaldehydes (1 eq.) using phthalimide-N-sulfonic acid (PhtSA) or isatin-N-sulfonic acid (IsSA), as solid-acid catalysts, afforded the mentioned compounds with good to excellent yields in short times.Briefly, we have introduced tw...

The three components one pot synthesis of 2-amino-4H-benzo-[b] -pyran derivatives were obtained in good to excellent yields within short reaction time by condensing dimedone, aldehydes and malanonitrile or ethylcyanoacetate using a catalytic amount of (diacetoxyiodo)benzene as hypervalent iodine in aqueous ethanol under reflux conditions have been discussed. This aqua mediated Knoevenagel-cyclo...

Stable crystalline phosphorus ylides are obtained in excellent yields from the 1:1:1 addition reactionbetween hydantoins or thiohydantoins and dialkyl acetylenedicarboxylates in the presence oftriphenylphosphine. These phosphoranes undergo smooth intramolecular Wittig reaction followedby an electrocyclic ring opening to produce dialkyl (E)-2-(2,5-dihydro-5,5-diaryl-2-thioxo-1H-imidazol-4-yl)fum...