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  • Author or Editor: Leandro S. de M. Miranda x
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Journal of Flow Chemistry
Authors: Ivaldo Itabaiana Jr, Ivana C. R. Leal, Leandro S. M. Miranda, and Rodrigo O. M. A. de Souza

Abstract

In this work, a three-step chemo enzymatic cascade reaction is reported for 1-monoacylglycerols from glycerol derived from biodiesel industry under continuous-flow conditions. Glycerol protection was performed using H2SO4/SiO2 (2.5% w/v) solid catalyst and acetone, generating 87% of solketal under 55 °C at 0.1 mL/min with glycerol–acetone ratio of 1.5:1. Coupled esterification between the formed solketal and stearic acid catalyzed by Rhizomucor miehei enzyme (RM IM) was able to maintain 90% of conversion until 1.5 M of substrate concentration at 0.1 mL/min flow rate and could be recycled up to 18 times. Final ketal cleavage was performed with the same H2SO4/SiO2 solid catalyst and the amount of water generated in the esterification reaction, whereas a flow rate of 0.2 mL/min was the best condition where the formation of 1-monoacylglycerol was maximized and byproducts were not detected.

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Journal of Flow Chemistry
Authors: Ingrid C. R. Costa, Ivaldo Itabaiana Jr., Marcella C. Flores, Ana Clara Lourenço, Selma G. F. Leite, Leandro S. de M. e Miranda, Ivana C. R. Leal, and Rodrigo O. M. A. de Souza

Abstract

The use of glycerol derived from biodiesel industry is an important development to add value to this actual waste. Several products can be obtained from glycerol, but acetins are very interesting molecules with a wide range of applications in pharmaceutical, cosmetics, food, and fuel industry. Herein we report our results on biocatalyzed batch and continuous-flow process for valorization of glycerol derived from biodiesel industry towards acetin production. Excellent results can be obtained with different selectivities depending on the nature of glycerol used and reaction conditions being able to produce monoacetin, diacetin, or triacetin depending on the reaction condition.

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Journal of Flow Chemistry
Authors: Raquel A. C. Leão, Raquel de O. Lopes, Marco A. de M. Bezerra, Mauro N. Muniz, Bruna B. Casanova, Simone C. B. Gnoatto, Grace Gosmann, Laszlo Kocsis, Rodrigo O.M.A. de Souza, and Leandro S. de M. Miranda

The use of continuous-flow chemistry has shown to be an important tool in improving API manufacture. In the present paper, we report the use of continuous-flow reactors in the synthesis of the bicyclic side chain of antiretroviral Darunavir.

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