El objetivo del estudio fue conocer y comprender el significado que le otorgan los(as) docentes del área a la Química Verde como perspectiva para su enseñanza. De este modo, permite proyectar líneas de investigación en la construcción de un conocimiento y enfoques didácticos de las ciencias, y para ser considerada como parte de los programas Ministeriales. La Química Verde, como área de investigación, se comprende como el desarrollo de metodologías para modificar los productos o procesos con la finalidad de reducir o eliminar los riesgos que existen para el medio ambiente y la salud. Among the scenarios assessed, the proposed chemical pathway represents the greenest alternative. A green metrics analysis was performed to ascertain the sustainability of the proposed chemical route and to compare it with previously reported studies for the SBL synthesis. Amberlyst™15 was the most promising catalyst among the tested ones, since it yields the highest conversion with very low side reactions extension. According to screening experiments, dense polymer network favors SBL formation.
Empirical equations relating conditions and yields were obtained, and response surface methodology analysis with subsequent multiobjective optimization allowed identification of optimal conditions to maximize simultaneously the yield of both reactants to SBL-that is high 1B initial concentration and temperature ranging 360–370 K. The optimal experimental conditions determined at 373 K and R°LA/1B = 0.5 render 1B and LA yields to SBL of 48.1% and 76.8%, respectively. Experiments were performed in a temperature range of 313–383 K with initial molar ratios of LA to 1B (R°LA/1B) from 0.4 to 3. Liquid-phase esterification of levulinic acid (LA) with 1-butene (1B) over ion-exchange resins was studied following an experimental design approach aimed at identifying the optimal conditions to synthesize sec-butyl levulinate (SBL) through the proposed reaction pathway. The merits of spreadsheet tools are presented from decision making in route selection all the way to fast and accurate proofreading of the final plan chosen. Problems in the reporting of chemical syntheses in scientific journals and patents are discussed as well as setting guidelines for their standardization and normalization. The take-home message is that targeted optimization is a multivariable problem that requires synergistic maximization and minimization of key variables. A summary of trends in achieving green chemistry strategies is presented, including an unbiased method of ranking plans using a suite of parameters, ring construction strategies, and implications on the development of new kinds of smart structure search databases. Data mining of the original literature covered the period 1828–2010. This paper presents the first announcement of a comprehensive database consisting of green metrics calculations for 1060 plans to 220 targets of interest to the chemical industry in the following categories: commodity industrial chemicals, pharmaceuticals, agrichemicals, dyestuffs and colorants, natural products, flavorings, fragrances, and sweeteners, and molecules of theoretical interest.
After 20 years of green chemistry research, a complete algorithm for the determination of material and synthetic strategy efficiencies for synthesis plans to any chemical target has been achieved.
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