ANALKIN(AGDC): a multipurpose computational program for the kinetic resolution of multicomponent mixtures (static and dynamic)

Classic and multivariate modeling treatment of the kinetics and mechanism of isomerization of 5‐cholesten‐3‐one catalyzed by sodium ethoxide

“…This technique allows one to collect a number of very precise experimental data which enables both the classic and multivariate modeling kinetic treatments. We checked the correct fulfillment of the Beer-Lambert law by both isomers, obtaining the molar absorption coefficients (ε 4 Taking into account the presence in the isomerization of ionic species (EtO − and Na + ), it was first necessary to evaluate the influence of ionic strength on the reaction rate. We carried out several kinetic experiments previously adding different concentrations of inert electrolyte within a concentration range of 10 −4 and 0.3 mol dm −3 .…”

“…In the present work, we performed an exhaustive study of the kinetics and mechanism of isomerization of 5-CHOL, catalyzed by ethoxide ions (EtO − ), in absolute ethanol medium applying a classic kinetic methodology and a multivariate modeling kinetic methodology. We structured the work according to the aims proposed: (a) determination of the experimental kinetic and thermodynamic parameters of activation by application of the classic kinetic treatment methodology; (b) confirmation of the validity of the mechanism considered appropriate after application of the steadystate method; (c) determination of the isomerization equilibrium constant from the kinetic data; (d) determination of the isomerization enthalpy; (e) application of a multivariate modeling kinetic methodology [3,4] to calculate the concentrations of the species (including those highly reactive intermediate species) and validation of the mechanism that best fitted the experimental kinetic data.…”

“…We have developed a technique based on the multivariate regression analysis whose origin was the KILET, a series of papers under the generic title "Computation in Kinetics" [10][11][12][13]. Later, we have designed at our laboratory * [14] the AGDC algorithm and later implemented in the corresponding multipurpose computational program, ANALKIN (AGDC) [4]. It has been successfully applied in many other different scientific fields [14,16] with different tasks, i.e.…”

“…We consider the kinetic treatment on two types of mixture [3,4]: static multicomponent mixtures (SMM), whose quantitative composition we wish to know is invariable and constant (classical mixtures) and dynamic multicomponent mixtures (DMM), whose quantitative composition under study varies over time, that is, all the components play the role of reagents and/or products of a chemical reaction induced by the addition of the reagents and whose kinetic processes are evaluated with a view to determine the concentrations of the all species, permitting the validation of the proposed model of the reaction (multivariate modeling kinetic). We performed the treatment by kinetic methodologies and later numerical computational analysis using a multivariate nonlinear regression technique, based in all cases on the use of the AGDC (controlled descent general algorithm) mathematical unconstrained optimization algorithm.…”

“…It is a robust algorithm that can be used for such purposes, both in a regression technique and in any other different ones as long as the aim is to search for the minimum of a function in the hyperspace defined by the parameters to be optimized. This package of calculation programs has been assigned the generic name of ANALKIN (AGDC) [4] because it is applied to chemical systems for ANALytic purposes, via the use of KINetic techniques, using the AGDC mathematical unconstrained optimization algorithm. The generic expression of a DMM according to the IUPAC recommendations [19] will be…”