the kinetics of the reactions between triphenylphosphine 1 and dialkyl acetylenedicarboxylates 2, in the presence of a nh-acid such as 5-nitroindazole 3,were studied. corresponding kinetic parameters to all reactions were evaluated, with the second order rate constant (k) values calculated. effects of solvent, temperature, and reactants (dialkyl acetylenedicarboxylates) structure and concentrat...

in order to investigate the effects of dimethylamino substituent at postion 2 of the dihydropyridine nucleus on its activity, dialkyl 1,4-dihydro-2-[2-(dimethy- lamino) ethyl]-6-methyl-4-(1-benzyl-2-alkylthio-5-imidazolyl)-3,5-pyrdinedicar- boxylates (6a-f) were synthesized. the synthesis was started from dialkyl 1,4- dihydro-2,6-dimethyl-4-(1-benzyl-2-alkylthio-5-imidazolyl)-3,5-pyridinedicar-...

The reactive intermediate generated by the addition of tert-butyl and 1,1,3,3-tetramethyl butyl isocyanide and cyclohexyl isocyanide to dialkyl acetylenedicarboxylate was trapped by 3-hydroxy pyridine to produce highly functionalized 4H-chromenes in fairly good  yields

The reactive intermediate generated by the addition of tert-butyl and 1,1,3,3-tetramethyl butyl isocyanide and cyclohexyl isocyanide to dialkyl acetylenedicarboxylate was trapped by 3-hydroxy pyridine to produce highly functionalized 4H-chromenes in fairly good  yields.

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 1:1 reactive intermediates produced in the reaction between alkyl isocyanides and dialkyl acetylenedicarboxylates were trapped with 2-thioxothiazolidin-4-one to generate to highly functionalized ketenimines. A series of new 2-thioxothiazolidin-4-one derivatives were synthesized in moderate yields. The advantages of the present method include good functional group tolerance and simple experi...

A mild and efficient synthesis of polysubstituted dihydro-2-oxypyrroles has been developed for the one-pot, four-component domino condensation of dialkyl acetylenedicarboxylate, formaldehyde and aromatic amines using Vanadium (V) oxide as the catalyst at ambient temperature. The use of Vanadium (V) oxide makes this process simple, more convenient, and environmentally friendly.