REVISITING THE NUCLEOPHILICITY CONCEPT IN A COMPREHENSIVE BIOMASS VALORIZATION EXPERIMENT: FROM PAPAYA SEEDS TO THIOUREA MOTIFS

• Autor(a) principal: Santos,Raquel V. dos
• Data de Publicação: 2019
• Outros Autores: Viana,Gil M., Moreira,Anderson Felipe S., Nóbrega,Vitor S., Silva,Vitor A. S. da, Malta,Luiz Fernando B., Aguiar,Lucia C. S., Senra,Jaqueline D.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Química Nova (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422019004800940
• topic: Green Chemistry; hands-on learning; third-year undergraduate students; Organic Chemistry

The recovery of waste materials with potential for synthetic transformations is a major field in science. However, just few experiments have been devoted to undergraduate students by exploring some consistent subjects in light of simple, natural resources. Nucleophilicity is a central subject in chemistry and there are significant synthetic models to exploit it in contrast to basicity. Here we present a laboratory experiment that utilizes hands-on research to be implemented in an organic chemistry lab by using benzyl isothiocyanate (BITC) from papaya seeds as raw material for the preparation of thioureas in a fast and visually indicative experiment. Subjects such as green chemistry, extraction methods, nucleophilicity, chromatography and NMR spectroscopy can be emphasized in order to implement a project-based approach. This experiment shows flexibility concerning the procedures and the use of biomass raw materials towards the reinforcement of a research-like experience and critical-thinking skills.