some 2-iminothiazolidin-4-ones have been synthesized by the reaction of dialkyl acetylenedicarboxylates with thiosemicarbazones. the reaction was performed in the presence of 10 mol% of triphenylphosphine and tetrabutylammonium bromide as a phase transfer catalyst in water as a green solvent. all the synthesized compounds were characterized by their physical and spectral data.

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 reactant...

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...

Ionic liquids such as 1,3-dialkylimidazolium salts make excellent catalysts and solvents for synthesis of dialkyl 2-(dialkoxyphosphoryl)-3-(1-oxo-1-H-phthalazin-2-yl)succinates from 2H-phthalazin-1-one, dialkyl acetylenedicarboxylates, and trialkyl phosphites. Under similar conditions, triphenyl phosphite led to dialkyl 2-(diphenoxyphosphoryl)-3-(1-oxo-1-H-phthalazin-2-yl)succinates. The ionic ...

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...

Cyclooctyne and cycloocten-5-yne undergo, at room temperature, a 1,3-dipolar cycloaddition with dialkyl acetylenedicarboxylates 1a,b to generate furan-derived short-lived intermediates 2, which can be trapped by two additional equivalents of 1a,b or alternatively by methanol, phenol, water or aldehydes to yield polycyclic products 3b-d, orthoesters 4a-c, ketones 5 or epoxides 6a,b, respectively...

The reaction of stoichiometric amounts of dialkyl acetylenedicarboxylates with alkyl isocyanides and 5,5-diaryl thiohydantoins in toluene and catalytic amount of p-TSA afforded imidazo[2,1-b][1,3]thiazines in good overall yields

A series of structurally diverse spiro 1,3-oxazines were conveniently prepared from three-component reaction conjugated imines, dialkyl acetylenedicarboxylates (DAAD), and N,N'-disubstituted parabanic acids in dry dichloromethane without catalyst. Initially, various imines synthesized aniline derivatives with cinnamaldehyde. Subsequently, DAAD N,N'-substituted led to mixture the corresponding s...

The 1,3-dipolar cycloaddition reactions of the electron deficient boron azide, (C6F5)2BN3 (1) with the electron-poor acetylenes RO2CC≡CCO2R (R = Me, Et) afforded the new mono- and bis-1,2,3-triazole derivatives and .

reaction of dialkyl acetylenedicarboxylates 1a-c andpyrrole derivatives 2a-e in the presence of triphenylphosphite (tpp) was investigated and the effect of the pyrrole substitution was established. diastereoselectivity is observed with pyrroles, 2a,b, yieldingphosphonate ester derivatives 3a-f and 4,and their relative configuration is determined by 1h/13c and 31p nmr and confirmed by single x-r...