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Hydroxyalkylation of Cyclic Imides with Oxiranes Part III. Mechanism of the Reaction in Presence of Sodium Hydroxide Catalyst

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Open Journal of Physical Chemistry 2018年第3期8卷 67-79页

作者： Jacek lubczak renata lubczak Dorota Naróg Faculty of Chemistry University of Technology Rzeszów Poland

The kinetics of reaction between cyclic monoimides (succinimide, phtalimide, and glutarimide) with ethylene and propylene oxides in presence of sodium hydroxide was studied. The effect of substrate and catalyst concentrations on the course of the reaction was investigated. Kinetics of reaction was studied by dilatometry, i.e. by measuring volume contraction of reaction mixture. The kinetic law describing the reaction of imides with oxiranes is: . where ccat, cAH and cB are concentrations of catalyst, imide, and oxirane, respectively. The relative reactivity of imides and oxiranes was: GI > PI ≥ SI and EO > PO. The reaction mechanism was proposed based upon experimentally determined rate law for the reaction of cyclic monoimides and oxiranes as well as analytical and instrumental analysis of products. The elementary reaction between oxirane and imide anion is rate determining step. The imide anion is formed by hydrogen cation transfer into catalytic hydroxide anion from dissociated NaOH. In the consecutive elemental reaction an imidate anion attack on the oxirane molecule occurs. It is the slowest stage of the reaction, limiting the entire process. All the studied reactions obey the same mechanism as can be concluded from isokinetic relationship of studied systems)

关键词： Imides Oxiranes Catalyst Kinetic Reactivity of Reagents Thermodynamic Parameters Mechanism of Reaction

Trifuntional Oligoetherols and Polyurethane Foams with Carbazole Ring

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Hydroxyalkylation of Cyclic Imides with Oxiranes Part I. Kinetics of Reaction in Presence of Triethylamine as Catalyst

Open Journal of Organic Polymer Materials（有机高分子材料期刊） 2012年第1期

作者： renata lubczak

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Open Journal of Physical Chemistry 2012年第2期2卷 88-96页

作者： Jacek lubczak Faculty of Chemistry Rzeszów University of Technology Rzeszów Poland

Literature describes kinetics of reactions of alcohols, phenols, carboxylic acids, amines and amides with oxiranes such as ethylene oxide and propylene oxide. However, there is no information regarding kinetic of reaction of imides with oxiranes. In this article the kinetics of the reaction of cyclic monoimides: succinimide, phtalimide, and glutarimide, with ethylene and propylene oxides in presence of triethylamine in aprotic solvent was studied. The rate laws for those processes were established based upon on dilatometric measurements. I was said that cyclic monoimides react with oxiranes in presence of triethylamine to give N-(2-hydroxyalkyl)imides as major product. This product react further with oxiranes in consecutive reaction. The kinetics of the reaction of cyclic mono-imides with oxiranes obey the following rate law: V = k1/2 c1/2cat c3/2imide c1/2oxirane. Based upon kinetic data the following orders of reactivity of imides and oxiranes were obtained: phtalimide ≥ succinimide > glutarimide and ethylene oxide > propylene oxide. The solvent (DMF, DMSO and dioxane) effect was also studied. From temperature dependences the thermodynamic parameters: activation energy, enthalpy and entropy from linear Eyring plots were obtained.

关键词： Imides Oxiranes Kinetic Reactivity Influence of Solvents

Hydroxyalkylation of Cyclic Imides with Oxiranes. Part II. The Mechanism of Reaction in Presence of Triethylamine

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Open Journal of Physical Chemistry 2012年第2期2卷 97-102页

作者： Jacek lubczak Faculty of Chemistry Rzeszów University of Technology Rzeszów Poland

The mechanism of reaction of cyclic monoimides with oxiranes was established based upon kinetic studies and product analysis. It has been established that the reaction proceeds through initial formation of an adduct of imide and triethylamine. The crucial bond in adduct has ionic character;in non-aqueous solvents it is present as ion pair, while in water the adduct dissociate and free ions are present. The adduct enables the proton transfer from imide to oxirane. The rate determining step is reaction of imide and this adduct. Different values of entropy of transition states obtained from thermodynamic calculations suggest slightly different structure of transition state of rate determining step.

关键词： Imides Oxiranes Mechanism Kinetics Non-Kinetics Evidences