Synthesis Of Stable Phosphorus Ylides Research Articles

One-pot synthesis of stable phosphorus ylides by three-component reaction between arylglyoxals, phosphines and barbituric or Meldrum’s acid

One-pot synthesis of stable phosphorus ylides by three-component reaction between arylglyoxals, phosphines and barbituric or Meldrum’s acid

Diastereoselective Synthesis of Stable Phosphorus Ylides by a Three-Component Reaction between Triphenylphosphine, Dialkyl Acetylenedicarboxylates and 3-(Arylsulfonylhydrazono)Butanoates

Protonation of the reactive 1:1 intermediate produced in the reaction between dialkyl acetylenedicarboxylates and triphenylphosphine by 3-(arylsulfonylhydrazono)butanoates leads to vinylphosphonium salts which undergo Michael addition with the conjugate base of the CH-acid to produce highly functionalised, salt-free phosphorus ylides in a diastereoselective manner and excellent yields.

Solvent-Free Conditions as an Eco-Friendly Strategy for Synthesis of Organophosphorus Compounds

A series of diverse NH- and CH-acids are used for a one-pot synthesis of stable phosphorus ylides and 1,4-diionic organophosphorus compounds by trapping of the zwitterionic intermediate from the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates under solvent-free conditions. The structural geometry for one of the products was confirmed by single crystal X-ray diffraction analysis. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.

Efficient, Simple Synthesis of Stable Phosphorus Ylides Derived from 4-Aryl Urazoles

Crystalline phosphorus ylides are obtained in nearly quantitative yields from the 1:1:1 addition reaction between triphenylphosphine, dialkyl acetylenedicarboxylates, and 4-aryl urazoles.

An efficient method for synthesis of stable phosphorus ylides and 1,4-diionic organophosphorus compounds in the presence of sodium dodecyl sulfate in aqueous media

Stable crystalline phosphorus ylides and 1,4-diionic organophosphorus compounds were obtained in good to excellent yields from the 1:1:1 addition reaction between triphenylphosphine, dialkyl acetylenedicarboxylates and β-dicarbonyl or heterocyclic compounds, such as diethyl malonate, acetyl acetone, 1,3-diphenyl propane-1,3-dione, 1,3-dimethylbarbituric acid, meldrum’s acid, 2-benzoxazolinone, benzotirazole, and 2-thiazoline-2-thiol in the presence of sodium dodecyl sulfate as a surfactant in water. Green synthesis, mild conditions, decreasing timescale of reaction, low cost, and easy workup are the main advantages of this method.

Three-component reaction between triphenylphosphine, dialkyl acetylenedicarboxylate and 4-amino-5-alkyl-2,4-dihydro-1,2,4-triazole-3-thiones: an efficient one-pot synthesis of stable phosphorus ylides

Protonation of the reactive 1:1 intermediate produced in the reaction between dialkyl acetylenedicarboxylates and triphenylphosphine by 4-amino-5-alkyl-2,4-dihydro-1,2,4-triazole-3-thione leads to vinylphosphonium salts which undergo Michael addition with the conjugate base of the NH-acid to produce highly functionalized, salt-free phosphorus ylides in excellent yields.

Chemoselective Synthesis of Stable Phosphorus Ylides from 6-Azauracil and Mechanistic Investigation of the Reaction by UV Spectrophotometry

Stable crystalline phosphorus ylides were obtained in excellent yields from the 1:1:1 addition reaction between triphenylphosphine and dialkyl acetylenedicarboxylates, in the presence of NH-acids such as 6-azauracil. These stable ylides exist in solution as a mixture of two geometrical isomers as a result of restricted rotation around the carbon–carbon partial double bond resulting from conjugation of the ylide moiety with the adjacent carbonyl group. To determine the kinetic parameters of the reactions, they were monitored by UV spectrophotometry. The second order fits were automatically drawn, and the values of the second order rate constants (k2) were automatically calculated using standard equations. At the temperature range studied, the dependence of the second order rate constant (Ln k2) on reciprocal temperature was in agreement with the Arrhenius equation. This provided the relevant plots to calculate the activation energy of all the reactions. Furthermore, useful information was obtained from studies of the effect of solvent, structure of reactants (different alkyl groups within the dialkyl acetylenedicarboxylates), and also concentration of reactants on the rate of reactions. The proposed mechanism was confirmed according to the obtained results, and a steady-state approximation and first step (k2) of the reaction was recognized as a rate-determining step on the basis of experimental data.

An efficient method for synthesis of organophosphorus compounds in aqueous media

A convenient and facile one-pot synthesis of stable phosphorus ylides and 1,4-diionic organophosphorus compounds is reported by the reaction of triphenylphosphine, dialkylacetylenedicarboxylates and N–H, C–H or S–H acids in the presence of polyethyleneglycol (PEG), β-cyclodextrin (β-CD), glycerine (Gly) or ethyleneglycol (EG) in water. This methodology is of interest due to the use of water as a solvent, thus minimizing the cost operational hazards, and environmental pollution.

One-pot synthesis of stable phosphorus ylides using aldehyde phenylhydrazone derivatives

One-pot synthesis of stable phosphorus ylides using aldehyde phenylhydrazone derivatives

Synthesis of Stable Phosphorus Ylides from 6-Chloro-2-Benzoxazolinone and Kinetic Investigation of the Reactions by Uv Spectrophotometry

Stable crystalline phosphorus ylides were obtained in excellent yields from the 1:1:1 addition reactions between triphenylphosphine and dialkyl acetylenedicarboxylates, in the presence of an NH-acid, such as 6-chlorobenzoxazolinone. These stable ylides exist in solution as a mixture of two geometrical isomers as a result of restricted rotation around the carbon-carbon partial double bond resulting from conjugation of the ylide moiety with the adjacent carbonyl group. To determine the kinetic parameters of the reactions, they were monitored by UV spectrophotometry. The second order fits were drawn and the values of the second order rate constant ( k2) were calculated automatically using standard equations within the program. Over the temperature range studied, the dependence of the second order rate constant (Ln k2) on reciprocal temperature was in a good agreement with the Arrhenius equation, leading to the activation energies of all reactions. Furthermore, useful information was obtained from studies of the effect of solvent, the structure of reactants (different alkyl groups within the dialkyl acetylenedicarboxylates) and also the concentration of reactants on the rate of reactions. The proposed mechanism is consistent with the results obtained and the steady state approximation, and the first step ( k2) of reaction was recognized as the rate-determining step on the basis of experimental data.

A facile synthesis of stable phosphorus ylides derived from 3,6‐dibromocarbazole and kinetic investigation of the reactions by UV spectrophotometry technique

AbstractStable crystalline phosphorus ylides were obtained in excellent yields from the 1:1:1 addition reaction between triphenylphosphine and dialkyl acetylenedicarboxylates, in the presence of NH‐acid, such as 3,6‐dibromocarbazole. These stable ylides exist in solution as a mixture of two geometrical isomers as a result of restricted rotation around the carbon–carbon partial double bond, resulting from the conjugation of the ylide moiety with the adjacent carbonyl group. To determine the kinetic parameters of the reactions, they were monitored by UV spectrophotometry. The second‐order fits were drawn, and the values of the second‐order rate constant (k2) were calculated using standard equations within the program. At the temperature range studied, the dependence of the second‐order rate constant (ln k2) on reciprocal temperature was in a good agreement with the Arrhenius equation. This provided the relevant plots to calculate the activation energy of all reactions. Furthermore, useful information was obtained from studies of the effect of solvent, structure of reactants (different alkyl groups within the dialkyl acetylenedicarboxylates), and also the concentration of reactants on the rate of reactions. The proposed mechanism was confirmed according to the obtained results and a steady‐state approximation and the first step (k2) of reaction was recognized as a rate‐determining step on the basis of the experimental data. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:723–732, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20501

A Practical Method for Synthesis of Stable Phosphorus Ylides in the Presence of Polyacrylamide in Aqueous Media

Stable crystalline phosphorus ylides were obtained in good to excellent yields from the 1:1:1 addition reaction between triphenylphosphine, dialkyl acetylenedicarboxylates and β -dicarbonyl or heterocyclic compounds such as, diethyl malonate, acetyl acetone, 1, 3-dimethylbarbituric acid, meldrum's acid, 2-benzoxazolinone, pyrrole-2-carboxaldehyde, benzotriazole, 5-methyl benzotriazole, and 5-chloro benzotriazole, in the presence of polyacrylamide in water. The green and mild reaction conditions, medium to short reaction time, low cost, ready preparation are the main advantages of this method.

A simple synthesis of stable phosphorus ylides from reaction between triphenylphosphine and acetylenic esters in the presence of CH-acid compounds

A simple synthesis of stable phosphorus ylides from reaction between triphenylphosphine and acetylenic esters in the presence of CH-acid compounds

One-Pot Synthesis of Stable Phosphorus Ylides by Three-Component Reaction between Dimethyl Acetylenedicarboxylate, Semicarbazones, and Triphenylphosphine

Protonation of the reactive 1:1 intermediate, produced in the reaction between dimethyl acetylenedicarboxylate and triphenylphosphine, by aromatic aldehyde semicarbazones leads to vinylphosphonium salts, which undergo Michael addition with the conjugate base of the NH-acid to produce highly functionalized, salt free phosphorus ylides in excellent yields.

Synthesis of stable phosphorus ylides from 3, 5-dimethylpyrazole and kinetic investigation of the reactions by UV spectrophotometry

Synthesis of stable phosphorus ylides from 3, 5-dimethylpyrazole and kinetic investigation of the reactions by UV spectrophotometry

Synthesis of Stable Phosphorus Ylides by the Reaction of Ph3P With Activated Acetylenes in the Presence of Dimethyl Methoxymalonate

Triphenylphosphine reacts with dimethyl methoxymalonate in the presence of alkyl propiolates or dialkyl acetylenedicarboxylates to produce trialkyl 3-(1,1,1-triphenyl-λ5-phosphanylidene)-1-propene-1,1,2-tricarboxylates or tetraalkyl 3-(1,1,1-triphenyl-λ 5-phosphanylidene)-1-propene-1,1,2,3-tetracarboxylates in good yields.

A Simple Synthesis of Stable Phosphorus Ylides Derived from 2-Benzoxazolinone and 2-Mercaptobenzoxazole

The reaction of triphenylphosphine with dialkyl acetylenedicarboxylates in the presence of a strong SH-acid or NH-acid, such as 2-mercaptobenzoxazole and 2-benzoxazolinone, has been studied. In some cases, stable phosphorus ylides are obtained in excellent yields. The ylide moiety of these compounds is strongly conjugated with the adjacent carbonyl group, and the rotation about the partial double bond in (E) and (Z) geometrical isomers is slow on the NMR time scale at an ambient temperature. Thus, these exist as a mixture of geometrical isomers.

A Facile Synthesis of Stable Phosphorus Ylides Derived from Harmin, Harman, and Carbazole.

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An Efficient Synthesis of Stable Phosphorus Ylides Derived from Triphenylphosphine, Dialkyl Acetylenedicarboxylates, and an NH-Acid

Stable crystalline phosphorus ylides were obtained in excellent yields from the 1:1:1 addition reaction between triphenylphosphine and dialkyl acetylenedicarboxylates in the presence of strong NH-acids, such as benzotriazole, 5-methylbenzotriazole, 5-chlorobenzotriazole, pyrrole, 2-acetylpyrrole, pyrrole-2-carboxaldehyde, 4-nitro-acetanilide, 4-methoxyacetanilide, 4-bromoacetanilide, 4-methylacetanilide, 2-methyl-acetanilide, and 2,6-dimethylacetanilide. These stable ylides exist in a solution as a mixture of two geometrical isomers as a result of the restricted rotation around the carbon–carbon partial double bond resulting from the conjugation of the ylide moiety with the adjacent carbonyl group.

A Simple Synthesis of Stable Phosphorus Ylides from Indole and Some of Its Derivatives

Stable crystalline phosphorus ylides were obtained in excellent yields from the 1:1:1 addition reaction between triphenylphosphine and dialkyl acetylenedicarboxylates in the presence of strong NH acids, such as indole and 2-methyl indole, 3-methyl indole, and 5-boromo indole. These stable ylides exist in a solution as a mixture of two geometrical isomers as a result of the restricted rotation around the carbon–carbon partial double bond resulting from the conjugation of the ylide moiety with the adjacent carbonyl group.