Kinetics and mechanism study of aniline addition to ethyl propiolate

Abstract

The kinetics of the addition reaction of aniline to ethyl propiolate in dimethylsulfoxide (DMSO) as solvent was studied. Initial rate method was used to determine the order of the reaction with respect to the reactants, and pseudo-first-order method was used to calculate the rate constant. This reaction was monitored by UV-Vis spectrophotometer at 399 nm by the variable time method. On the basis of the experimental results, the Arrhenius equation for this reaction was obtained as log k = 6.07 − (12.96/2.303RT). The activation parameters, E a , H # , G # , and S # at 300 K were 12.96, 13.55, 23.31 kcal mol −1 and −32.76 cal mol −1 K −1 , respectively. The results revealed a first-order reaction with respect to both aniline and ethyl propiolate. In addition, based on the experimental results and using also density functional theory (DFT) at B3LYP/6-31G* level, a mechanism for this reaction was proposed. C 2005 Wiley Periodicals, Inc. Int J Chem Kinet 38: [144][145][146][147][148][149][150][151] 2006

Characterization of Kemer L4 meteorite using Raman spectroscopy, X-ray diffraction, magnetization measurements and Mössbauer spectroscopy

“…Ethyl propiolate (HC≡CCOOCH2CH3, EP) is the ethyl ester of propiolic acid consisting of an ethyl ester group attached to an acetylenic fragment (H−C≡C−). The compound is broadly used in organic synthesis, in particular in dipolar cycloaddition reactions leading to heterocycles such as pyrazoles, which possess a large range of applications in the pharmaceutical industry as well as in the agrochemical field, [1][2][3][4][5][6][7][8][9] and as nucleophile in conjugate addition reactions such as those allowing selective carboncarbon bond formation, which are particularly relevant in chemical synthesis and molecular design. [10][11][12][13] The compound is also used as a derivatizing agent for the thiol group for the analysis of varietal thiols in wine.…”

Addition Reactions: Polar Addition

“…In addition, combination of the experimental results and calculations using density functional theory (DFT) at the B3LYP/6-31G * level, a mechanism for this reaction was proposed. 181 An efficient double conjugate addition of ethane and propane dithiols in the presence of sodium methoxide to propargylic carbonyl compounds (127) has been developed. The corresponding amino-substituted propargylic aldehydes afforded piperidine derivatives.…”